Dissertations / Theses on the topic 'Placental outcomes'

Current ACOG guidelines recommend exercise during a low-risk pregnancy for 30 minutes on most, if not all days of the week. However, little is known about how the volume of exercise performed during pregnancy affects fetoplacental size. In addition, the confounding effects of maternal nutrient intake and weight gain, and how they interact with exercise volume to influence fetoplacental size have not been appropriately addressed. Therefore, the purpose of this study was to examine the effects of varying maternal exercise volumes on neonatal birthweight and placental volume, while addressing the influence of maternal nutrient intake and weight gain. Subjects evaluated for this study included pregnant women who walked during gestation (n=26), performed non-walking aerobic exercise during gestation (n=30), or remained as sedentary controls (n=32). At 16, 20, 24, 28, 32, 36 weeks gestation, women recorded their nutrient intake for 3 consecutive days. Additionally, they kept monthly exercise logs indicating the type and duration of their exercise. Nutrient variables calculated included average daily Calorie intake, average daily carbohydrate intake, average daily protein intake, average daily fat intake, and average daily fiber intake. Exercise volume was calculated as the average number of minutes per week spent performing exercise. Latent growth modeling was the statistical procedure used to analyze how change in maternal exercise volume and nutrient intake throughout gestation affects neonatal outcomes. Neonatal outcomes measured were birthweight, corrected birthweight for gestational age, sex, race, and socioeconomic status, and placental volume at delivery. Maternal walking volume had no effect on newborn birthweight or corrected birthweight, while it was inversely related to placental size at birth. Maternal non-walking aerobic exercise volume was inversely related with newborn birthweight, while there was a trend toward an inverse relationship with corrected birthweight and placental volume. Controlling for Calorie intake strengthened the relationship between any form of exercise volume and infant birthweight. Calorie intake, carbohydrate intake, and protein intake were all positively related to infant birthweight. Fiber intake was significantly inversely related to placental volume. Finally, maternal exercise volume and nutrient intake were not related to maternal weight gain. This data suggests that neonatal outcome will be affected by variations in exercise protocol. In addition, nutrient intake is a potentially confounding variable that should be examined when undertaking studies addressing the role of maternal exercise on neonatal outcome.

Background: Nausea and vomiting in pregnancy (NVP) is considered one of the ultimate reproductive health dilemmas and often misunderstood both biologically and conceptually. This phenomenon occurs in approximately eighty percent of pregnancies worldwide and there are many theories relating to the cause of symptoms, however, no origin has been identified. Morning sickness will be discussed primarily within a physiological framework that focuses on maternal characteristics, placental structure, and related birth outcomes. Interestingly, vomiting in pregnancy appears to be unique to the human species, which from an evolutionary medical perspective is thought to be the result of human adaptation to varying internal and external environments. Some human adaptations or the consequential effects of these adaptations are not always viewed as favourable, from our twenty-first century medical point of view. Women with an absence of NVP symptoms in pregnancy are understudied and therefore, an essential and informative addition to this cohort. Aims: The primary focus of this research project was to investigate NVP in relation to maternal characteristics, placental structure, and birth outcomes in singleton pregnancies. This study also included an important subset of expectant mothers with no reported NVP symptoms. Characteristics of morning sickness for expectant mothers with pregnancies resulting from ART and non-ART conception were examined. Psychosocial outcome variables and morning sickness status were compared using three specific measures from the maternal health questionnaire (MHQ) [Social Provision Scale (SPS), Pregnancy Distress Scale (PDQ) and the Perceived Stress Scale (PSS)], and the Edinburgh Postnatal Depression Scale (EPDS) from the maternal medical records. Data generated from the MHQ, gross placental morphology, maternal and natal medical records were examined to determine the associations between morning sickness, placental structure, and birth outcomes (e.g., low birth weight, placental weight, and birth weight to placental weight ratio). A unique addition to this study was the consideration of the placental microbiome as a potential contributing factor to differences in women with different NVP status. Methods: To investigate NVP characteristics and examine the role of the human placenta and NVP status, 625 expectant mothers with singleton pregnancies were recruited from two major hospitals in Perth, Western Australia. Pregnancies were the result of natural and assisted conception and expectant mothers participated in a cross- sectional survey consisting of a MHQ, and gross placental examination using gross morphologic analysis. On completion of placental analyses, data from the maternal and natal medical records were collected and characteristics compared for women with differing nausea and vomiting status. The characteristics of NVP were identified through statistical analyses of the data, including significant medical, clinical, and psychosocial factors. Gross placental morphology measures and birth outcomes were compared according to NVP status. Results: NVP was experienced by most expectant mothers in this cohort (79%) with 21% of women experiencing no NVP and 3% clinically diagnosed with hyperemesis gravidarum (HG). Nausea was the most prevalent symptom followed by food avoidance and women were more likely to report the frequency of these symptoms as continuous, while retching and vomiting were episodic in nature. Symptoms were self-rated as moderate to severe, and all risk factors were positively correlated with NVP. Women with HG recorded associated variables including increased symptom frequency and severity, medication use and a majority of the risk factors from the MHQ. The severity and frequency of symptoms were significantly associated with a number of maternal characteristics including age of menarche, increased maternal weight/obesity on first antenatal booking and admission for delivery of the baby. Increased psychosocial measures noted for women with NVP were related to the frequency and severity of symptoms. This was consistent for women who experienced HG and had pregnancies resulting from ART. ART treatments were also associated with an increased frequency and severity of symptoms. Women experiencing NVP reported higher overall scores for the Pregnancy Distress Questionnaire and Perceived Stress Scale when compared to women who had no NVP, and evaluation of the Social Provision Scale identified women with NVP had lower self-rating scores for Nurturance and Attachment. Women in this study delivered normal healthy babies, with normal BW/PWR and ponderal index ranges. Placental measures were similar for NVP status groups across this cohort and a majority fell within the 10th and 90th centiles for BW and placental weight. Evaluation of placental weight for women with clinically diagnosed HG in ART and non-ART pregnancies found that women who conceived naturally and experienced HG had an increased trimmed placental weight (grams). Women with HG who conceived using ART were more likely to have a lower placental weight. This was the first study to explore the association between the placental amniochorionic microbiome and morning sickness status in women with singleton pregnancies. Significant differences in microbial diversity were noted between NVP status groups. Women with NVP had a higher species diversity and those in the No NVP group having a lower microbial diversity. Clinical relevance: This comprehensive study has produced new and insightful information, highlighting the role of maternal characteristics and placental development in maternal health and birth outcomes. A detailed examination of NVP and the relationship between NVP symptoms, have highlighted the need for research that explores symptom frequency and severity rather than the presence or absence of symptoms alone. Examination of medical and clinical characteristics for women with and without NVP have provided new theoretical understanding and this current research provides evidence-based findings linking NVP and placental anatomy that are important for perinatal health. Future research examining the biological mechanisms and NVP symptom expression would be valuable. As part of reproductive health, ongoing research that promotes clinical understanding and the effective management of nausea and vomiting in pregnancy will decrease patient distress and foster practitioner confidence. Documentation of key concepts related to the physiology of nausea and vomiting in pregnancy can provide an understanding of the pathways that lead to NVP. Expectant mothers will be empowered by having access to updated information promoting maternal and natal health outcomes. Importantly, information should be provided to partners, family, friends, and caregivers to assist, nurture and support all expectant mothers.

Maternal obesity and diabetes increase the risk of delivering large for gestational age infants (LGA), who have higher risk of long term obesity or metabolic syndrome [1]. As the underpinning mechanisms of how fetal growth is regulated by the placenta remain unclear [2], this thesis has investigated placental responses to high maternal BMI and gestational diabetes. Spanish pregnant women recruited at 20 gestational weeks were classified according to pre-pregnancy BMI as control (BMI<25kg/m2; n=59), overweight (BMI=25-30kg/m2; n=29) or obese (BMI>30kg/m2; n=22), and gestational diabetes status (GDM) classified at 28 weeks. Maternal anthropometry and gestational weight gain (GWG) were measured during pregnancy. Placenta, cord blood, newborn antrophometry and infant weight were sampled or measured. Expression of genes involved in placental energy sensing pathways, folate transporters and DNA methylation was determined using real-time PCR, and placental triglyceride concentrations, lipid peroxidation and genomic DNA methylation patterns measured. Data were analysed according to their parametric distribution by Kruskal-Wallis or 1-way ANOVA. Despite lower GWG, a greater proportion of obese women exceeded recommended weight gain [3], had higher placental weight and increased numbers of LGA infants. Maternal hyperinsulinaemia and hyperglycaemia with obesity were accompanied by unchanged placental IGFR1 and ISR1 expression, similar cord blood glucose and triglyceride concentrations. Placental mTOR was halved with obesity, whilst SIRT1 and UCP2 gene expression were 1.8 and 1.6 fold upregulated respectively with no differences in TBARS concentrations. Hyperleptinaemia in obese women resulted in unchanged placental leptin and leptin receptor expression, but higher cord blood leptin and monocyte concentrations with placental hypermethylation of genes involved in the immune response. Lower folate concentrations in obese mothers led to similar cord blood folate, and decreased placental FRα, but raised DNMT1, mRNA expression. No major differences were observed with GDM, probably due to small sample size. In conclusion, it appears that the placenta can protect the fetus of obese women by increasing antioxidant capacity, compensating for maternal hyperglycaemia and lower folate. However, maternal obesity was associated with enhanced cord blood leptin and monocyte concentrations, increased placental weight and more LGA delivery, leaving infants at ongoing risk of increased adiposity and inflammation. Therefore, current studies are currently exploring these interacting aspects.

Many abnormalities of the placenta are reported to be significant in the setting of maternal health problems and adverse fetal/neonatal outcomes. In specific clinicopathological circumstances - eg vascular lesions in the growth restricted fetus – correlation does exist between the placental lesion and the clinical event. Relationships between “lower grade” placental lesions and clinical outcomes are less clear. Reports of associations between selected abnormalities and clinical outcomes are largely based on retrospective case control studies: the clinical groups studied tend to be high-risk. Understanding of the significance of these lesions in the wider population is lacking. This study reports on the clinical events and placental lesions documented in 1119 unselected women delivering at the conclusion of a singleton pregnancy in a single obstetric centre. Study methodology was such that the cohort comprised low-risk mothers delivering at or close to term. The incidence of potentially adverse obstetric and neonatal events in the study population was low. 97% delivered at term. Mean birth weight was 3485 g; mean Apgar scores were 9 at 1 minute and 10 at 5 minutes. 5.9% of infants required admission to neonatal intensive care. When classified in accordance with current standard reporting guidelines, 71% of placentas were classified as normal. Inclusion of lower grade histological lesions in the reporting schedule reduced the percentage of histologically normal placentas to 58%. Funisitis was found to be significantly correlated with adverse neonatal outcome. A number of other placental lesions - including cord coiling <10th and >90th centiles, placental infarction, villitis of unknown etiology and lower grades of acute placental inflammation - were not found to be associated with adverse obstetric or neonatal events. It is concluded that a number of placental lesions may not be relevant to adverse pregnancy outcomes in a low-risk population.

Mounting evidence suggests prenatal stress can affect child development. Clinical studies of this concept, termed fetal programming, focus predominantly on early childhood. Also, little is known about the mechanisms underlying how maternal stress is transmitted to the fetus. This thesis will test if maternal anxiety during pregnancy is associated with (1) behavioural outcomes from childhood to early adolescence, (2) cortisol output in adolescence and (3) an altered placental phenotype. For Studies 1 and 2 participants were drawn from the Avon Longitudinal Study of Parents and Children (ALSPAC). Psychometric data from 9,871 mother child pairs (5,098 males, 4,773 females) were analysed using latent growth curve analysis. A subsample of the ALSPAC children aged 15 years (n = 899) provided saliva samples on three days at waking, +35mins, after school and before bed, for later cortisol analysis. For Study 3 a new cohort of women (n= 73) was recruited. Maternal psychometric data was collected one day prior to elective caesarean section, and the placenta collected after delivery. Study 1 showed that maternal prenatal anxiety was associated with conduct and emotional problems, and symptoms of ADHD at age 13 years, after allowing for a range of confounders, including postnatal anxiety. There were marked sex differences in the developing patterns. Saliva cortisol demonstrated a marked diurnal profile with a clear sex difference at age 15. Higher maternal prenatal anxiety was associated with a reduced cortisol awakening response. High levels of maternal prenatal anxiety were associated with reduced placental expression and activity of the cortisol metabolising enzyme 11β-Hydroxy steroid dehydrogenase 2 (11β-HSD2) and also with reduced placental weight. This thesis provides evidence that maternal prenatal anxiety can affect behavioural and neuroendocrine outcomes in adolescence. It also provides preliminary evidence that maternal anxiety is associated with alterations in the function of the placenta, which may underlie some aspects of fetal programming. These findings have public health implications. Increasing awareness about the lasting effects of prenatal anxiety may ultimately benefit mothers, the care they receive and their families.

Obese pregnant women have increased risk of a number of pregnancy complications, including poor maternal health, fetal growth restriction (FGR) and fetal demise. The success of pregnancy is dependent on precise regulation of the immune response within the utero-placental environment. Rats as a model for human related pregnancy complications are beginning to be widely used because of the similarities between these species in terms of trophoblast invasion and spiral artery remodeling. However our knowledge of immune cells and cytokine localization in the rat utero-placental tissue relating to these processes is limited. Therefore our first aim was to characterize the immune cell populations, such as uterine natural killer (uNK) cells, neutrophils and macrophages in the rat utero-placental unit at two crucial gestational ages relevant to trophoblast invasion and spiral artery remodeling, gestational day (GD) 15 and GD18. In addition, we characterized the cytokine distribution of TNFα, IFNγ and IL-10 in the utero-placental tissue at both above mentioned gestational ages. Our study has demonstrated co-localization of TNFα and IFNγ with uNK cells in the perivascular region of the spiral arteries in the rat mesometrial triangle. Neutrophils were localized at the maternal fetal interface and in the spiral artery lumen of the rat mesometrial triangle at both gestational ages. TNFα and IL-10 demonstrated a temporal change in the localization from GD15 to GD18 which coincides with the leading edge of trophoblast invasion into the mesometrial triangle. The results of the current study furthers our knowledge of the localization and temporal expression of uterine immune cells and relevant cytokines, and provides a base to research the function of these immune cells and cytokines during rat pregnancy as a model to study human pregnancy and complications related to immune functions. Since obesity is associated with a peripheral and systemic pro-inflammatory state in humans, our second objective was to investigate whether maternal obesity could alter the utero-placental and systemic immune response in the rats. To characterize maternal obesity induced changes in uterine immune state we used pregnant rats fed a control diet (normal weight; CD) or a high fat diet (obese; HFD) at GD15 and GD18. We performed immunohistochemistry to localize TNFα and IL-10, and quantified the levels of TNFα, IL-1β and IL-10 in the uterine tissue by immunoassay. To assess the systemic immune state, circulating levels of pro-inflammatory cytokine MCP-1 were assessed by immunoassay. We demonstrated an increased concentration of the pro-inflammatory marker TNFα and a reduced anti-inflammatory IL-10-positive cell distribution in the rat mesometrial triangle in response to a HFD. In addition increased circulating MCP-1 was observed in the HFD-fed dams at both gestation ages. HFD induced obesity in our rat model leads to an increase in uterine and systemic pro-inflammatory markers. These markers have demonstrated the potential to alter utero-placental development. Pregnancy complications such as FGR and fetal demise have been shown to be associated with impaired placental development as a result of altered trophoblast invasion and aberrant maternal spiral artery remodeling. Therefore, our third aim was to compare these parameters between the CD-fed rats and HFD-fed rats at GD15 and GD18. Early trophoblast invasion was increased by approximately 2-fold in HFD-fed dams with a concomitant increase in the expression of matrix metalloproteinase-9 protein, a mediator of tissue remodeling and invasion. By late gestation reduced trophoblast invasion was observed in HFD-fed dams. Furthermore, we also observed in late gestation significantly higher levels of smooth muscle actin surrounding the uterine spiral arteries of HFD-fed dams, suggesting impaired spiral artery remodeling. We also determined the impact of human serum from obese mothers on trophoblast invasion. We compared the invasion of HTR-8/SVneo cells treated with pooled first-trimester serum from obese women with or without fetal growth restriction vs. cells treated with serum from normal-weight women with or without fetal growth restriction. First-trimester serum from obese pregnant women reduced invasion of the trophoblast cell line HTR8/SVneo compared to serum from normal-weight pregnant women. Taken together, the results of this study suggest that maternal obesity can negatively influence crucial utero-placental development processes resulting in the poor pregnancy outcomes and increased fetal demise. To summarize, the HFD increased the pro-inflammatory marker TNFα which was associated with altered trophoblast invasion profiles and impaired vascular remodeling. These disturbances in utero-placental development were also associated with decreased birth weights (indication of FGR) and increased rates of stillbirths in our obese rat model. In conclusion, we have made progress in defining the influence of maternal obesity (HFD) on utero-placental development. The importance of these studies is evident since FGR represents a leading cause of perinatal morbidity and mortality. Furthermore, FGR fetuses have an increased risk of becoming obese in their lifetime as a result of fetal programming, therefore resulting in the propagation of a transgenerational obesity cycle. Therefore by understanding the mechanisms by which maternal obesity influences utero-placental development leading to FGR, we may be able to impact short term morbidity and prevent the programming of obesity in future generations. In addition, characterization of maternal obesity’s influence on utero-placental development will also help in the search for therapeutics or intervention strategies to help optimize fetal growth and improve pregnancy outcomes in obese women.

Background: There is an unsubstantiated conviction among clinicians that a significant reduction In amniotic fluid volume is a poor prognostic sign for pregnancy, even when it is an isolated finding. This belief has led to the inculcation of serial ultrasound assessments of amniotic fluid volume into the antenatal assessment of fetal well being with the aim of improving perinatal outcomes by closer monitoring and earlier delivery. In reality, there is no strong evidence base for this practice, while there are significant risks associated with premature delivery. There may also be cost and resource implications for the practice. Objective: The aim of this thesis was to investigate whether isolated oligohydramnios is significantly associated with adverse pregnancy outcomes in otherwise uncomplicated pregnancies, and to investigate the underlying associated maternal, fetal and placental aetiological factors. Materials and Methods: Amniotic fluid volumes were measured using ultrasound in 3328 low-risk pregnancies between 19 and 41 weeks. These were otherwise uncomplicated pregnancies recruited at the antenatal booking visit following a normal 1st trimester screening result (a negative 11-14 week combined nuchal translucency ultrasound and maternal serum-biochemistry fetal structural and chromosomal abnormality screening test). Maternal characteristics (age, parity, ethnicity, socioeconomic status, weight, smoking and alcohol consumption) during the course of the pregnancy, Placental characteristics (site, position and maturity), and Fetal renal blood flow parameters were also studied and analysed for possible associations. Results: Isolated oligohydramnios occurred more frequently with advancing maternal age and lower parity. However, maternal ethnicity, weight and socioeconomic status did not have any direct influence on the occurrence of isolated oligohydramnios and neither did the maternal life style factors studied. Increasing placental maturity was significantly associated with significantly reduced amniotic fluid but neither the placental site nor location was. There was a significant association between oligohydramnios and poor perinatal outcome as judged by meconium staining of amniotic fluid during labour, emergency Caesarean delivery for fetal compromise, an increased requirement for neonatal resuscitation and endotracheal intubation. In the population of pregnancies studied, there was no significant correlation between isolated oligohydramnios and a suspicious or pathological cardiotocogram during labour. However, a low birth weight less than 2500 g at birth, admission to the neonatal intensive care unit, a prolonged length of neonatal intensive care unit stay, and perinatal deaths were all significantly associated with oligohydramnios. No association was seen with either a low Apgar score or a low fetal arterial cord blood pH. Conclusion: This study showed that an isolated reduction in amniotic fluid volume even in an otherwise uncomplicated pregnancy is significantly associated with a poor perinatal outcome, and can therefore not be safely ignored. This finding justifies the continued assessment of amniotic fluid volumes.

This retrospective case-control study was designed to investigate the relationship between placental localization and intrauterine growth restriction (IUGR). Pregnant women with an anatomic survey from January 1, 2000, to December 31, 2005, and delivery of the pregnancy at Yale-New Haven Hospital (YNHH) were identified using clinical and billing records. Multiple gestation, fetal anomaly, and incomplete medical information were reasons for exclusion. Cases (N=69) were consecutive pregnancies with evidence of IUGR (estimated fetal weight <10th percentile for gestational age) at last follow-up ultrasound. Randomly selected controls (N=258) from the same time period had no evidence of IUGR. Maternal, ultrasound, delivery, and perinatal data were collected by retrospective medical record review, and IUGR cases and non-IUGR controls were compared using the Students t-test, Wilcoxon test, Chi-square analysis, Fishers exact test, and ANOVA. Placental location was determined from the anatomic survey record (obtained at 18.4 ± 1.2 weeks gestation in the IUGR group and 18.2 ± 1.0 weeks gestation in the control group; P=0.18). Multivariate logistic regression with adjustment for confounders was used to investigate the association between IUGR and placental localization. Consistent with known predictors of IUGR, the IUGR group had a higher proportion of black women (36.4% vs. 19.8%, P=0.03), chronic hypertension (26.0% vs. 3.5%, P<0.001), and hypertensive disorders of pregnancy (36.2% vs. 5.0%, P<0.001). Mean birth weights of IUGR and non-IUGR pregnancies differed by 2 kilograms (3244 ± 625 grams vs. 1277 ± 637 grams, P<0.001). IUGR infants were more likely to receive antenatal steroids, deliver preterm, deliver by cesarean section, and be admitted to neonatal intensive care. In both IUGR and non-IUGR pregnancies, the placenta was most commonly anterior or posterior. Unilateral placentas were three times more common in the IUGR group than in the non-IUGR group (17.4% vs. 5.0%, P=0.01). IUGR pregnancies were over four times as likely as control subjects to have unilaterally-located placentas compared to anterior placentas (OR 4.8, 95% confidence interval, 1.9-11.7). Adjusting for ethnicity, chronic hypertension, and hypertensive disorders of pregnancy did not affect this finding (OR 4.6, 95% confidence interval 1.6-13.5). In conclusion, we compared a group of 69 IUGR pregnancies to 258 non-IUGR controls and found intrauterine growth restriction to be associated with unilateral placentation.

Les pathologies vasculaires placentaires sont fréquentes et graves. La forme maternelle prédominante est la pré-éclampsie et la forme fœtale le retard de croissance intra-utérin. Les questions posées autour de ce sujet concernent tout d'abord la prédiction de la survenue de ces pathologies suffisamment tôt afin de permettre une surveillance rapprochée, une administration de corticoïdes et une prise en charge dans une maternité de niveau adaptée. La prévention de la survenue et de la récidive ainsi que le traitement de ces pathologies la phase constituée sont aussi des problématiques encore non résolues. Notre objectif était de travailler sur ces différentes questions pa l'intermédiaire de trois études : l'étude ANGIOPRED), l'étude VOLUPLA et l'étude GROWTH. Les résultats de ces travaux et une revue d la littérature mettent en évidence une perturbation des facteurs de l'hémostase et des facteurs angiogéniques dans la pré-éclampsie et dans le retard de croissance. L'association des facteurs maternels, échographiques, angiogéniques et sériques constitue un modèle prédictif efficace principalement du fait d'une excellente valeur prédictive négative. Le volume placentaire est corrélé au taux de D- Dimères et est intéressant pour la prédiction des pathologies vasculaires placentaires. De nouveaux travaux devront poursuivre l'étude d la prédiction, de la prévention et du traitement des pathologies liées au placenta. Le traitement est notamment l'objet de l'étude Growth qui vise à évaluer l'efficacité de l'énoxaparine dans le traitement du retard de croissance vasculaire constitué
Placenta-mediated adverse pregnancy outcomes are frequent and severe pathologies whose predominant maternal form is preeclampsia and fetal form, intrauterine growth retardation. The questions asked about this subject concern first of all the prediction of the occurrence of its pathologies in a sufficiently early way to allow for close monitoring, administration of corticosteroids, and management in an appropriate level of maternity. The prevention of the occurrence and recurrence and the treatment of its pathologies in the constituted phase are also unresolved problems. Our objective was therefore to work on its various questions through three studies: the ANGIOPREI study, the VOLUPLA study and the GROWTH study. The results of his work and of the literature show that the factors of haemostasis anc angiogenic factors are disturbed in preeclampsia and in growth retardation. The association of maternal, ultrasound, angiogenic and serum factors constitutes a predictive model that is effective mainly by an excellent negative predictive value. The placental volume is correlated with the D-dimer level and is interesting for placenta-mediated adverse pregnancy outcomes prediction. New studies will have to continue the exploration of the prediction, prevention and treatment of this pathologies related to the placenta. The treatment is notably the object of the study Growth which aims to evaluate the effectiveness of the Enoxaparin for the treatment of constituted vascular growt retardation

Iron and zinc deficiency during pregnancy is common among women in low-income nations. In such settings, prenatal nutritional intervention is encouraged to improve pregnancy outcome. The impact of the intervention on transporter proteins involved in fetal nutrient supply is unexplored. This study investigated gene expression of some transporter proteins involved in fetal nutrient supply in the placenta. In a trial in rural Gambia, pregnant women at <20weeks of gestation were randomised to 4 nutritional intervention arms: i) Iron and folic acid (FeFol), representing the usual care ii) Multiple micronutrients (MMN) iii) Protein energy (PE) iv) MMN and PE (PE+MMN). All the intervention arms contained 60mg iron and 400μg of folic acid. FeFol and MMN interventions were given in tablet format, whereas PE and PE+MMN were in food format (lipid-based nutrient supplement- LNS). Maternal blood samples collected at booking, 20 and 30 weeks of gestation were assessed for iron levels, and zinc levels measured only the later samples. Gene expression of proteins involved in fetal iron, zinc, amino acid and glucose transport were measured on placental samples collected at birth. LNS (PE and PE+MMN) intervention was associated with low maternal iron status in late pregnancy and increased placental mRNA expression of the primary iron-uptake protein, transferrin receptor 1(TfR1). Intervention arms with no supplementary zinc (FeFol and PE) had lower maternal plasma zinc levels and increased placental mRNA expression of intracellular zinc-uptake proteins, ZIP1, ZIP4 and ZIP8. Different nutritional intervention strategies are associated with changes in maternal iron and zinc status during pregnancy and corresponding changes in the gene expression of placental iron and zinc uptake proteins. This might suggest differential fetal intrauterine response to the interventions. Understanding the role of the placenta in the delivery of nutrients to the fetus is important when considering intervention strategies.

The high incidence of pregnancy loss is a major issue facing the cattle industry. Use of in vitro fertilized (IVF) bovine embryos has become increasingly popular to help alleviate several of these reproductive issues and provide a means to enhance genetic gain for production traits. An uterine paracrine factor cocktail containing epidermal growth factor (EGF), fibroblast growth factor 2 (FGF2), and insulin-like growth factor 1 (IGF1) (collectively termed EFI) was recently identified as a means for improving in vitro derived bovine embryo development and trophectoderm cell numbers. The objectives of this work were to determine if EFI treatment during in vitro bovine embryo culture improves transferable embryo quality and post-transfer placental and fetal development. For each replicate (3 total), slaughterhouse-derived bovine oocytes were matured and fertilized in vitro. At day 4 post-fertilization, ≥8 cell embryos were harvested, pooled, and exposed to either the EFI treatment (10ng/ml EGF, 10ng/ml FGF2, 50ng/ml IGF1) or carrier only (1% Bovine Serum Albumin). At day 7, individual embryos were transferred to estrous synchronized beef cattle. Artificial insemination (AI) was completed on a subset of cows. The EFI treatment increased (P<0.05) the percentage of transferable embryos. Pregnancy rate at day 28 post-estrus was similar among treatments. Circulating concentrations of pregnancy-associated glycoproteins (PAGs) were determined from plasma harvested at day 28, 42 and 56. Transrectal ultrasonography was used to measure fetal crown-rump length (CRL) at day 42 and 56 and to determine fetal sex at day 60. There were no main effect differences observed across days for PAG concentration. Fetus sex by ET/AI group interactions were absent at day 28 but existed at days 42 and 56 (P<0.05). At both days, this interaction reflected fetus sex-dependent changes within the ET control group, where PAG concentrations were greater (P<0.05) in male fetuses than female fetuses. No CRL differences or interactions existed among fetal sex and pregnancy group. In summary, addition of the EFI cocktail during bovine embryo culture improved the quality of transferable embryos, but did not affect placental function or embryonic/fetal development. Increasing the numbers of transferable embryos is of value given the cost of in vitro embryo production, but no apparent increases in embryo or placental competency were detected. The EFI treatment increased (P<0.05) the percentage of transferable embryos.
Master of Science

Orientador: Débora Cristina Damasceno
Banca: Marilza Vieira Cunha Rudge
Banca: Estela Maris Andrade Forell Bevillacqua
Banca: Renée Laufer Amorim
Banca: Teresa Cristina França Sartori
Resumo: Avaliar os efeitos do diabete moderado nos parâmetros reprodutivos maternos e no desenvolvimento placentário-fetal em ratas Wistar. Metodologia: No dia do nascimento, 147 ratas Wistar foram distribuídas aleatoriamente em dois grupos experimentais: Grupo não-diabético (Controle, n=45) - recebeu o veículo; Grupo diabético (STZ, n=102) - recebeu 100 mg streptozotocin/kg. Na fase adulta, as ratas foram acasaladas e, no dia 0 de prenhez, foram incluídas ratas controle que apresentassem glicemia abaixo de 120 mg/dL e, para o grupo diabete moderado, glicemia entre 120 e 300 mg/dL. Em diferentes momentos da prenhez, glicemia e peso corpóreo foram verificados. No 21º dia de prenhez, as ratas foram anestesiadas para coleta de sangue para dosagem de insulina e, em seguida, foi realizada laparotomia para retirada e pesagem dos fetos e placentas. Os dados maternos e fetais foram analisados por Twoway ANOVA seguida do Teste t. Os recém-nascidos (RN) foram classificados em pequenos, adequados e grandes para idade de prenhez e as comparações entre os grupos foram realizadas segundo o Teste de Qui-quadrado. As ratas STZ apresentaram glicemias maiores nos dias 0 e 14 de prenhez, menor número médio de fetos vivos, implantações e de corpos lúteos, aumento nas taxas de perdas embrionárias pós-implantação, no peso placentário e na proporção de RN pequenos (PIP) e grandes (GIP) para idade de prenhez, redução de RN AIP e inalteração nas concentrações de insulina. Portanto, o diabete de intensidade moderada alterou a glicemia materna no início da prenhez, que deflagrou alterações no organismo materno e/ou no desenvolvimento inicial do embrião, afetando sua implantação e futuro desenvolvimento placentário e fetal.
Abstract: To evaluate the mild diabetes effects on the maternal reproductive outcome and placental-fetal development in female Wistar rats. Methodology: At the birth day, 147 female rats were randomly distributed in two experimental groups: 1) Non-diabetic Group (Control, n=45) - received the vehicle; 2) Diabetic Group (STZ, n=102) - received 100 mg streptozotocin/kg. At the adult phase, the female rats were mated and, at the day 0 of pregnancy, they were included in the control group when presented glycemia below 120 mg/dL and, in the group STZ when showed glycemia between 120 and 300 mg/dL. In different moments of the pregnancy, glycemia and body weight were verified. At day 21 of pregnancy, the rats were anaesthetized to collect blood samples for insulin determination and, soon afterwards, the laparotomy was carried out to withdraw and weigh the fetuses and placentas. The maternal and fetal dates were analyzed by Two-way ANOVA followed by t Test. The newborns (NB) were classified in small, appropriate and large for gestational age and the comparisons between the groups were accomplished according to Qui-square Test. Rats STZ presented higher glycemia at days 0 and 14 of pregnancy, lower numbers of alive fetuses; implantations and corpora lutea; increased rate of embryonic losses, placental weight and proportion of small NB (SGA) and large (LGA); reduced rate of AGA NB and unaltered insulin concentrations. Therefore, the mild diabetes altered the maternal glycemia in the early pregnancy, which caused changes in the maternal organism and/or in the early development of the embryo, impairing its implantation and future placental and fetal development.
Doutor

El metabolisme monocarbonat i els elements traça essencials afecten al desenvolupament i resultat de l'embaràs. Es desconeixen els efectes de diversos polimorfismes del metabolisme monocarbonat (MTHFR c.665C>T, BHMT c.716G>A, SLC19A1 c.80G>A i MTRR c.66A>G) durant l'embaràs i la seva possible modulació segons l'estat en folat; i quins factors estan associats amb les concentracions d'elements traça (zinc, coure, seleni i ferro) en la placenta. Aquests aspectes dels esmentats polimorfismes i elements traça s’han estudiat en 617 embarassos del Reus-Tarragona Birth Cohort i 218 placentes. Amb alt estat en folat eritrocitàri a ≤12 setmanes gestacionals (SG), i en folat plasmàtic des de les 15SG, l’MTHFR c.665C>T no va haver tenir cap efecte sobre l'homocisteïna plasmàtica. Els genotips variants de BHMT c.716 tenien menor concentració de dimetilglicina des de la meitat de l'embaràs, i a principis de l'embaràs si l'estat en folat plasmàtic era alt. Homozigots variants de MTRR c.66 van tenir major concentració d'homocisteïna plasmàtica a principis de l'embaràs, però això no es veia en els tercils extrems de folat plasmàtic. Les concentracions en placenta de zinc, coure i seleni estaven positivament correlacionades entre si, i negativament associades al pes al néixer. Les fumadores durant l'embaràs van tenir majors concentracions de coure i seleni. La ingesta d'aquests elements traça de la dieta i/o suplements no es va associar amb les seves concentracions en placenta. Les concentracions plasmàtiques de cobalamina a ≤12SG i d'homocisteïna al part es van associar negativa i positivament, respectivament, amb les de coure en la placenta. L'al•lel normal de MTHFR c.665 del neonat i la concentració de coure en la placenta es van associar positivament amb el creixement intrauterí restringit. Els polimorfismes i la seva modulació segons l'estat en folat, i elements traça en placenta estudiats estan associats amb canvis en el metabolisme i resultat de l'embaràs.
El metabolismo monocarbonado y los elementos traza esenciales afectan al desarrollo y resultado del embarazo. Se desconocen los efectos de varios polimorfismos del metabolismo monocarbonado (MTHFR c.665C>T, BHMT c.716G>A, SLC19A1 c.80G>A y MTRR c.66A>G) en el embarazo y su posible modulación según el estado en folato; y qué factores están asociados con las concentraciones de elementos traza (zinc, cobre, selenio y hierro) en la placenta. Se estudiaron estos aspectos de dichos polimorfismos y elementos traza en 617 embarazos del Reus-Tarragona Birth Cohort y 218 placentas. Con alto estado en folato eritrocitario a ≤12 semanas gestacionales (SG), y en folato plasmático desde las 15SG no se observó el efecto de MTHFR c.665C>T en la homocisteína plasmática. Genotipos variantes de BHMT c.716 tuvieron menor concentración de dimetilglicina desde la mitad del embarazo, y esto ocurrió también a principios del embarazo si el estado en folato plasmático era alto. Homozigotos variantes de MTRR c.66 tuvieron mayor concentración de homocisteína plasmática a principios del embarazo, pero esto no ocurría en los terciles extremos de folato plasmático. Las concentraciones en placenta de zinc, cobre y selenio estaban positivamente correlacionadas entre sí, y negativamente asociadas al peso al nacer. Fumadoras durante el embarazo tuvieron mayores concentraciones de cobre y selenio. La ingesta de estos elementos traza de la dieta y/o suplementos no se asoció con sus concentraciones en placenta. Las concentraciones plasmáticas de cobalamina a ≤12SG y de homocisteína en el parto se asociaron negativa y positivamente, respectivamente, con las de cobre en la placenta. El alelo normal de MTHFR c.665 del neonato y la concentración de cobre en la placenta se asociaron positivamente con el crecimiento intrauterino restringido. Los polimorfismos y su modulación según el estado en folato, y elementos traza en placenta estudiados están asociados con cambios en el metabolismo y resultado del embarazo.
One carbon metabolism and essential trace elements affect foetal development and pregnancy outcome. The effects of several highly prevalent one carbon metabolism polymorphisms (MTHFR c.665C>T, BHMT c.716G>A, SLC19A1 c.80G>A and MTRR c.66A>G) in pregnancy and their possible modulation by folate status, and which factors are associated with the placenta trace element concentrations (zinc, copper, selenium and iron), are unknown. These aspects of the aforementioned polymorphisms and trace elements were studied in 617 pregnancies of the Reus-Tarragona Birth Cohort and 218 placentas. With high erythrocyte folate status at ≤12 gestational weeks (GW) and with high plasma folate status from 15GW on, the homocysteine-enhancing effect of MTHFR c.665C>T was not observed. Lower plasma dimethylglycine in BHMT c.716 variant genotypes was found at mid-late pregnancy, and this was also true for early pregnancy if plasma folate status was high. MTRR c.66 variant homozygotes had higher plasma homocysteine concentration at early pregnancy, and after plasma folate status stratification this was not observed in the extreme tertiles. Placenta concentrations of zinc, copper and selenium were positively correlated, and negatively associated with birth weight. Smoking during pregnancy was associated with higher copper and selenium concentrations. Intake of these trace elements from food and/or supplements was not associated with their concentrations in placenta. Plasma cobalamin at ≤12GW and homocysteine at labour were negatively and positively, respectively, associated with placenta copper concentrations. MTHFR c.665 normal allele in the neonate and placenta copper concentration were positively associated with intrauterine growth restriction. These studied polymorphisms and their modulation by folate status, and the placenta trace elements, are associated with metabolic changes and pregnancy outcome.

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Avaliar os efeitos do diabete moderado nos parâmetros reprodutivos maternos e no desenvolvimento placentário-fetal em ratas Wistar. Metodologia: No dia do nascimento, 147 ratas Wistar foram distribuídas aleatoriamente em dois grupos experimentais: Grupo não-diabético (Controle, n=45) - recebeu o veículo; Grupo diabético (STZ, n=102) - recebeu 100 mg streptozotocin/kg. Na fase adulta, as ratas foram acasaladas e, no dia 0 de prenhez, foram incluídas ratas controle que apresentassem glicemia abaixo de 120 mg/dL e, para o grupo diabete moderado, glicemia entre 120 e 300 mg/dL. Em diferentes momentos da prenhez, glicemia e peso corpóreo foram verificados. No 21º dia de prenhez, as ratas foram anestesiadas para coleta de sangue para dosagem de insulina e, em seguida, foi realizada laparotomia para retirada e pesagem dos fetos e placentas. Os dados maternos e fetais foram analisados por Twoway ANOVA seguida do Teste t. Os recém-nascidos (RN) foram classificados em pequenos, adequados e grandes para idade de prenhez e as comparações entre os grupos foram realizadas segundo o Teste de Qui-quadrado. As ratas STZ apresentaram glicemias maiores nos dias 0 e 14 de prenhez, menor número médio de fetos vivos, implantações e de corpos lúteos, aumento nas taxas de perdas embrionárias pós-implantação, no peso placentário e na proporção de RN pequenos (PIP) e grandes (GIP) para idade de prenhez, redução de RN AIP e inalteração nas concentrações de insulina. Portanto, o diabete de intensidade moderada alterou a glicemia materna no início da prenhez, que deflagrou alterações no organismo materno e/ou no desenvolvimento inicial do embrião, afetando sua implantação e futuro desenvolvimento placentário e fetal.
To evaluate the mild diabetes effects on the maternal reproductive outcome and placental-fetal development in female Wistar rats. Methodology: At the birth day, 147 female rats were randomly distributed in two experimental groups: 1) Non-diabetic Group (Control, n=45) - received the vehicle; 2) Diabetic Group (STZ, n=102) - received 100 mg streptozotocin/kg. At the adult phase, the female rats were mated and, at the day 0 of pregnancy, they were included in the control group when presented glycemia below 120 mg/dL and, in the group STZ when showed glycemia between 120 and 300 mg/dL. In different moments of the pregnancy, glycemia and body weight were verified. At day 21 of pregnancy, the rats were anaesthetized to collect blood samples for insulin determination and, soon afterwards, the laparotomy was carried out to withdraw and weigh the fetuses and placentas. The maternal and fetal dates were analyzed by Two-way ANOVA followed by t Test. The newborns (NB) were classified in small, appropriate and large for gestational age and the comparisons between the groups were accomplished according to Qui-square Test. Rats STZ presented higher glycemia at days 0 and 14 of pregnancy, lower numbers of alive fetuses; implantations and corpora lutea; increased rate of embryonic losses, placental weight and proportion of small NB (SGA) and large (LGA); reduced rate of AGA NB and unaltered insulin concentrations. Therefore, the mild diabetes altered the maternal glycemia in the early pregnancy, which caused changes in the maternal organism and/or in the early development of the embryo, impairing its implantation and future placental and fetal development.

Currently there is no test to accurately predict stillbirth. It is proposed that better identification of placental disease in utero may aid stillbirth prediction and prevention. Pregnancies complicated by reduced fetal movement (RFM) have increased risk of stillbirth. We hypothesised that RFM is a symptom of placental dysfunction associated with adverse pregnancy outcome (APO) and that this placental abnormality can be detected antenatally and used to identify fetuses at highest-risk of APO. We tested this hypothesis by: 1) comparison of ex vivo placental structure and function between APO RFM pregnancies and their normal outcome RFM counterparts, 2) comparison of in utero estimates of placental size, vascularity, vascular and endocrine functions obtained from placental ultrasound, Doppler waveform analysis and maternal circulating placentally-derived hormone concentrations, to their ex vivo correlates and 3) examination of the predictive potential of placental biomarkers at the time of RFM.Ex vivo placentas from APO RFM pregnancies, compared to normal outcome RFM counterparts, were smaller (diameter, area, weight and volume, p<0.0001), less vascular (vessel number and density, p≤0.002), with arteries that were less responsive to sodium nitroprusside (p<0.05), and with aberrant endocrine function (reduced tissue content and/or release of human chorionic gonadotrophin (hCG), human placental lactogen (hPL) and soluble fms-like Tyrosine Kinase-1 (sFlt-1), p<0.03). Placental volume (PV) ex vivo correlated with sonographic estimated PV (p<0.004), hPL, hCG and placental growth factor (PlGF) concentrations in the maternal circulation (p<0.03). Ex vivo villous vessel number and density correlated with Doppler impedance at the umbilical artery free-loop (UAD-F, p=0.02) and intraplacental arteries (p<0.0001) respectively, whilst UAD-F impedance correlated with arterial thromboxane sensitivity (p<0.04). Examination of placental structure and function at the time of presentation with RFM identified 15 independently-predictive biomarkers. Three potential predictive models, incorporating measures of placental size (PlGF), endocrine function (sFlt-1), arterial thromboxane sensitivity and villous vascularity (UAD-F), were proposed. Using these models, sensitivity for APO was improved from 8.9% with baseline care (assessment of fetal size and gestation) to up to 37.5% at a fixed specificity of 99% (p<0.05). This series of studies shows that antenatal placental examination is possible and improves identification of pregnancies at highest risk of stillbirth in a high-risk population by up to 29%. Therefore such tests merit further development to prospectively assess their ability to predict and prevent stillbirth itself.

La pollution atmosphérique et les évènements météorologiques sont reconnus pour avoir des graves conséquences sur la santé telles que la mortalité cardiovasculaire et respiratoire, et par conséquent représentent un enjeu majeur de santé publique. Des travaux plus récents ont suggéré un effet des expositions à ces facteurs environnementaux durant la période intra-utérine. La vie fœtale est déterminante pour le bon développement de l’enfant. L’exposition maternelle aux facteurs environnementaux pendant la grossesse pourrait avoir des conséquences sur les issues de grossesse et la santé à court ou long terme. Par ailleurs, les mécanismes biologiques qui pourraient expliquer l’effet des expositions environnementales sur les issues de grossesse indésirables sont à l’heure actuelle très peu connus. Les objectifs de la thèse étaient : 1) d’étudier les associations entre d’une part la température et l’humidité relative pendant la grossesse et d’autre part le poids de naissance, la durée de gestation et la prématurité ; 2) d’étudier les associations entre l’exposition maternelle aux polluant de l’air et aux évènements météorologiques pendant la grossesse et la méthylation de l’ADN placentaire en utilisant A) une approche agnostique et B) une approche avec a priori basée sur l’intégration de connaissances biologiques. Le premier objectif s’est appuyé les données issues de deux cohortes mère-enfant, EDEN (avec un recrutement à Poitiers et Nancy en 2003-2006) et PELAGIE (Bretagne, 2002-2006) soit au total 5185 couples mère-enfant ; le deuxième objectif s’est appuyé sur un échantillon de 668 femmes de la cohorte EDEN chez qui le placenta a été prélevé et le niveau de méthylation de son ADN caractérisé. Les données quotidiennes de température et d’humidité ont été obtenues de Météo-France et l’exposition à la pollution atmosphérique a été estimée par un modèle de dispersion atmosphérique. Différentes fenêtres d’exposition au cours de la grossesse ont été considérées. Des échantillons de placenta centraux ont été collectés à l’accouchement et la méthylation de l’ADN a été analysée en utilisant la puce Illumina 450K. Pour répondre au premier objectif, des modèles de régression linéaire et des modèles de Cox ont été réalisés. Pour répondre au second objectif, des modèles de régression linéaire robuste, notamment à l’échelle du génome entier, ont été réalisés en appliquant des méthodes de correction de tests multiples telles que Bonferroni et Benjamini-Hochberg. Nos résultats suggèrent un effet délétère de la température et l’humidité sur le poids de naissance et ne mettent pas en évidence d’association entre pollution atmosphérique et issues de grossesse. L’exposition aux polluants atmosphériques (NO2 et PM10) pendant la grossesse était associée à une diminution de la méthylation de l’ADN placentaire pour les gènes ADORA2B et ADARB2 ; le premier gène étant connu pour être potentiellement impliqué dans la pré-éclampsie et l’hypoxie de la femme enceinte et le deuxième étant potentiellement impliqué dans les troubles métaboliques chez l'adulte tels que la circonférence abdominale et l'IMC. Les résultats des approches agnostique et avec a priori étaient cohérents pour le gène ADORA2B. Nous n’avons pas identifié d’association entre les conditions météorologiques et la méthylation de l’ADN placentaire. A notre connaissance, nous sommes les premiers à avoir étudié l’association entre la méthylation de l’ADN dans le tissu placentaire et l’exposition prénatale aux polluants de l’air et aux conditions météorologiques en utilisant des données de l’épigénome entier. Ce travail de thèse ouvre de nouvelles voies possibles concernant les mécanismes d’actions des polluants environnementaux et fournit des pistes quant aux effets à long terme possibles de ces expositions
Nowadays, air pollution and weather conditions represent a major public health issue. It is recognized that they may have serious consequences for health especially in the most sensitive populations such as pregnant women. More recent studies have suggested an effect of exposure to these environmental factors during the fetal period. Fetal life is a critical period for the healthy development of the child. Maternal exposure to environmental exposures during pregnancy could have serious consequences on pregnancy outcomes and short- and long- term health. Furthermore, the biological mechanisms that could explain the effect of environmental exposures on adverse pregnancy outcomes are largely unknown up to now. The objectives of the thesis were: 1) to study the association between maternal exposure to temperature and relative humidity during pregnancy and birth weight, gestational duration and preterm birth; 2) to study the association between maternal exposure to air pollutants and meteorological conditions during pregnancy and placental DNA methylation using A) an agnostic approach and B) a priori approach based on integration of biological knowledge. The first part of this work relied on data from two mother-child cohorts EDEN (Poitiers and Nancy, 2003-2006) and PELAGIE (Britain, 2002-2006) corresponding to 5185 mother-infant pairs analyzed; and the second part relied on a sample of the EDEN cohort for which methylation data were available (n = 668). Daily data of temperature and humidity were obtained from Météo-France and pollution data were obtained using a dispersion model. Their exposure was averaged over different periods during pregnancy. Central placenta samples were collected at delivery and DNA methylation was analyzed using Illumina 450K chip. For the first objective, linear regression models and Cox models were used. For the second objective, robust linear regression models, especially across the genome-wide, were used and correction methods for multiple testing such as Bonferroni and Benjamini-Hochberg were applied. Our results suggest a deleterious effect of temperature and relative humidity on birth weight and did not show an association between air pollution and pregnancy outcomes. Exposure to air pollutants (NO2 and PM10) during pregnancy was associated with a decrease in placental DNA methylation for ADORA2B and ADARB2 genes; the first gene is known to be potentially involved in preeclampsia and hypoxia of the pregnant woman and the second being potentially involved in metabolic disorders in adults such as abdominal circumference and BMI. The results of agnostic and a priori approaches were consistent for ADORA2B gene. We did not found association between weather conditions and placental DNA methylation. To our knowledge, we are the first to study the association between DNA methylation in the placental tissue and prenatal exposure to air pollutants and weather conditions using data from the entire epigenome. This work opens up new possible pathways regarding mechanisms of action of environmental pollutants and provides pointers as to the possible long-term effects of these exposures

The prenatal period is a stage of special sensitivity to the adverse effects of environmental agents for the developing fetus. The human placenta is an organ that, in the interface between mother and fetus, plays a key role in fetal growth and development and, as such, affects the fetal programming underlying subsequent disease vulnerability in adulthood. There is increasing epidemiological evidence linking prenatal exposure to endocrine disrupting chemicals (EDCs) and adverse health outcomes in children, although mechanisms remain still unclear. Xenoestrogens are a group of endocrine disrupting chemicals that target the estrogenic signaling pathway and include a large number of compounds, both man-made and of natural origin, ubiquitously present in the environment, often at low doses. Xenoestrogen exposure has been related both in humans and in animal models to adverse health endpoints, most especially obesity and metabolic disorders, reproductive problems, increased risk for several types of cancers and neurobehavioral abnormalities. Prenatal epigenetic dysregulation has been proposed as a possible causal mechanism. The main objective of this thesis has been to evaluate the effects of prenatal exposure to mixtures of xenoestrogens on growth related and neuropsychological outcomes in children from the prospective Spanish birth cohort study INMA, INfancia y Medio Ambiente (Childhood and the Environment) Project, and to analyze whether in utero exposure to mixtures produces changes in placental DNA methylation, both globally or at specific genes and/or nearby regions. For that purpose, the Total Effective Xenoestrogen Burden (TEXB-alpha), a biomarker of the cumulative exposure to xenoestrogens, was measured in placental tissue using the E-Screen biossay. Information on birth outcomes was recorded by pediatricians or nurses at birth and at following time points, and neuropsychological assessment was conducted by trained psychologists using two different scales when children were around 2 and 4 years of age. DNA methylation was measured on DNA extracted from placenta for a sub-group of children using quantitative methods. We evaluated global DNA methylation by bisulfite pyrosequencing of several retrotransposons (repetitive elements that make up around 42% of the human genome); and genome-wide DNA methylation was scanned with a comprehensive array provided by Illumina, the HumanMethylation450 BeadChip, in which practically all human genes and many regulatory regions are represented. Associations were tested using linear regression, mixed-effects regression or robust linear regression models accordingly, always adjusting for potential confounders and sex specific effects were investigated. Overall, we found significant associations between TEXB-alpha exposure in boys but not in girls and the outcomes studied: higher TEXB-alpha levels were associated with increasing birthweight and with a decrease in motor performance at age 1-2 years, which did not persist at age 4. Additionally, we found some evidence that xenoestrogen exposure produced a decrease in placenta global DNA methylation in an Alu element in boys and, although non-significant after multiple testing correction, induced changes in DNA methylation in boys in CpG sites located in several genes (i.e. LRPAP1, HAGH, PPARGC1B,KCNQ1 and KCNQ1DN), previously associated either to birthweight and Type 2 Diabetes, obesity or to steroid hormone metabolism and signalling. Results from this work on chidren from the general Spanish population suggest that low-level exposure to mixtures of hormonally active estrogenic compounds may produce growth-related changes and some adverse effects on the early development of motor tasks in the male population, and are suggestive of epigenetic disruption in global methylation in the same group, while the association with specific genes in boys remains unclear and needs to be evaluated in larger samples and using alternative methods. This thesis has analyzed for the first time in an epidemiological study a biomarker of exposure to mixtures of xenoestrogens in placenta in relation to birthweight, children growth, body mass index and neuropsychological development, adding knowledge to the limited evidence that prenatal xenoestrogen exposure could be relevant in terms of children health outcomes, that epigenetic alterations may play a mechanistic role and highlights the importance to take into account possible sex-related vulnerability to EDCs during pregnancy.
El període prenatal és una etapa sensible als efectes de l’exposició a agents ambientals. La placenta humana, un òrgan que comunica la mare i el fetus i que, durant aquest període, juga un paper clau en el creixement i el desenvolupament fetal. Com a tal, la placenta podria estar implicada en alteracions fenotípiques ja visibles en la infància i amb possibles efectes en salut a llarg termini. Existeix evidència epidemiològica que relaciona l’exposició prenatal a pertorbadors endocrins (EDCs, de l’ anglés endocrine disrupting chemicals) amb diferents indicadors de salut infantil, tot i que els mecanismes d’acció són encara poc coneguts. Els xenoestrògens són un grup d’EDCs que interfereixen amb les vies de senyalització de les hormones estrogèniques. Inclouen un ampli ventall de compostos, alguns d’origen natural i d’altres sintètic, omnipresents en el medi ambient, sovint a baixes concentracions. Un nombre important d’estudis científics han trobat associacions, tant en humans com en models animals, entre l’exposició prenatal a aquests compostos i alteracions metabòliques, obesitat, problemes reproductius, un augment de risc de patir diferents tipus de càncer i alteracions en el desenvolupament de funcions neuropsicològiques. Un possible mecanisme molecular proposat per molts investigadors que podria explicar, almenys en part, aquestes associacions és l’alteració de patrons epigenètics durant el període prenatal. L’objectiu principal d’aquest projecte de tesi ha estat avaluar l’associació entre l’exposició prenatal a mescles de compostos xenoestrogènics i el pes al naixement, la velocitat de creixement durant els 6 primers mesos i l’índex de massa corporal als 14 mesos, així com el desenvolupament neuropsicològic a diferents edats en nens de la cohort espanyola de naixement INMA (INfància i Medi Ambient), i també estudiar si aquesta exposició produeix canvis en la metilació del DNA en la placenta, a nivell global i/o en gens específics o possibles regions reguladores del genoma. Amb aquest propòsit, vam mesurar en placenta l’efecte estrogènic degut a mescles de compostos ambientals mitjançant un biomarcador anomenat Total Effective Xenoestrogen Burden (TEXB-alfa) usant l’assaig E-Screen, basat en la proliferació de cèl.lules tumorals MCF que responen a estrògens. La informació referent al pes al néixer i altres variables de creixement va ser recollida per pediatres i/o infermeres i l’avaluació neuropsicològica va ser realitzada per psicòlegs entrenats amb experiència prèvia en l’administració de les dues escales utilitzades. En un subgrup de nens, es va analitzar la metilació del DNA en placenta amb diferents mètodes quantitatius. A nivell global la vam estimar mesurant el percentatge de citosines metilades en unes seqüències repetides que constitueixen fins a un 42% del total del genoma humà anomenades retrotransposons usant la tècnica de piroseqüenciació i, per altra banda, es van mesurar els nivells de metilació de forma quantitativa en un gran nombre de citosines distribuïdes al llarg de tot el genoma, incloent pràcticament tots els gens descrits i moltes regions reguladores, amb un array produït per la casa comercial Illumina anomenat HumanMethylation450 BeadChip. Les corresponents associacions van ser analitzades usant models de regressió lineals, models de regressió lineal mixta (per a tenir en compte mesures repetides o correlacionades) i regressions lineals robustes, ajustant per potencials variables confusores. En tots els casos es va estudiar l’existència d’efectes diferents en funció del sexe dels nens. Els resultats obtinguts en aquesta tesi mostren l’existència d’associacions entre l’exposició prenatal a TEXB-alpha i els diferents fenotips estudiats en els nens però no en les nenes: en aquests, nivells alts de TEXB-alpha es relacionaven amb un augment significatiu del pes al néixer i alteracions neuropsicològiques, concretament una disminució en les puntuacions de l’escala motora al voltant dels 2 anys, tot i que aquest últim efecte ja no el trobàvem als 4 anys d’edat. També vam observar una disminució en els nens amb nivells alts de TEXB-alpha en la metilació en placenta d’un element repetitiu anomenat AluYb8, que representa un indicador de la metilació global del genoma i, tot i no ser significatius a nivell estadístic, vam trobar canvis en la metilació en nens en uns CpGs situats en gens (LRPAP1, HAGH, PPARGC1B, KCNQ1 i KCNQ1DN) que en estudis anteriors s’havien relacionat amb el pes al néixer, la obesitat, la diabetis de tipus II i el metabolisme i la resposta a hormones esteroides com l’estrògen. Aquests resultats, obtinguts en població general infantil espanyola, suggereixen que l’exposició constant i a baixes dosis a mescles de compostos actius a nivell hormonal podrien afectar el creixement i tenir un impacte en el desenvolupament inicial de funcions cerebrals en la població masculina, i aporten evidència de canvis en els nivells de metilació global en aquesta població, mentre que les associacions observades en relació a gens concrets són incertes i caldran més estudis en altres cohorts més nombroses i validacions tècniques usant altres mètodes. Finalment, aquesta tesi ha realitzat per primer cop un estudi epidemiològic usant un biomarcador d’exposició conjunta a mescles de xenoestrògens en placenta en relació a variables de creixement i desenvolupament neuropsicològic, i aporta nou coneixement a l’evidència científica existent, tot i que limitada, de què l’exposició prenatal a xenoestrògens pot tenir un impacte en la salut infantil, que alteracions en la metilació del DNA podrien jugar un paper mecanístic en aquests efectes observats i, finalment, destaquen la importància d’estudiar la possible vulnerabilitat diferencial entre nens i nenes a l’exposició in utero a pertorbadors endocrins.

Abstract Despite improvements in peri- and neonatal care and an increase in the overall survival of very preterm infants, the incidence of neurologic sequelae has remained high. The pathogenesis of many brain imaging findings, such as white matter damage, WMD, is poorly understood. The factors predisposing to brain damage differ between term and preterm infants. More detailed information is needed of how brain imaging correlates with neurodevelopmental impairment after the neonatal period. The present study investigated the pre- and perinatal factors leading to brain damage and their effects on neurologic and neurodevelopmental outcome in very preterm children. We also analyzed the differences in umbilical cord serum cytokines in term and preterm children with cerebral palsy, CP. Furthermore, the correlations between the findings on diffusion-weighted imaging, DWI, measurements in brainstem auditory evoked potentials, and neurodevelopmental outcome were assessed. We demonstrated that pregnancies complicated by combined histologic chorioamnionitis and placental insufficiency independently predicted abnormal neurologic outcome at 2 years of corrected age. WMD additively predicted poor outcome. Isolated fetal inflammatory response, umbilical cord serum acute phase cytokines (IL-1α, IL-1β, IL-6, IL-8, TNF-α), did not associate with neurologic outcome in either term or preterm children. Instead, a cluster of cytokines different from acute phase cytokines were related to CP, and the protein profile differed between term and preterm children. Disturbed hemodynamics during the pre- and perinatal period affected outcome in very preterm infants. In severe placental insufficiency, fetal cardiac compromise associated with suboptimal neurodevelopmental outcome at 1 year of corrected age. In addition, several clinical factors characterising cardiorespiratory status after birth associated with abnormal neurologic outcome at 2 years of corrected age. We found the apparent diffusion coefficient, ADC, a quantitative measurement of water diffusion, in pons to correlate with the conduction rate of impulses travelling through the auditory tract. We also demonstrated a high value of ADC in corona radiata to associate with poor outcome in gross motor and eye-hand coordination skills at 2 years of corrected age. Both pre- and perinatal factors associate with later outcome in very preterm infants. An isolated fetal inflammatory response does not predict neurologic outcome. Findings on DWI in specific brain regions predict abnormal neurodevelopmental outcome
Tiivistelmä Huolimatta vastasyntyneisyyskauden parantuneista hoitotuloksista ja että yhä useampi hyvin ennenaikaisena syntynyt lapsi jää eloon, heidän neurologisen vammautuneisuuden ilmaantuvuus on edelleen korkea. Monien aivojen kuvantamislöydösten, kuten valkean aineen vaurion, syntymekanismit tunnetaan huonosti. Aivojen vaurioitumiselle altistavat tekijät eroavat täysiaikaisena ja ennenaikaisena syntyneillä lapsilla. Tarvitaan myös aiempaa yksityiskohtaisempaa tietoa aivojen kuvantamislöydösten merkityksestä lasten vastasyntyneisyyskauden jälkeiseen kehitykseen. Tässä tutkimuksessa selvitettiin raskauden- ja syntymänaikaisia tekijöitä, jotka vaikuttavat aivojen vaurioitumiseen hyvin ennenaikaisena syntyneillä lapsilla sekä näiden tekijöiden merkitystä lasten neurologiseen kehitykseen. Tarkastelimme myös napaveren seerumin välittäjäaineiden, sytokiinien, eroavuuksia täysiaikaisena ja ennenaikaisena syntyneillä CP-lapsilla. Lisäksi selvitimme diffuusiomagneettitutkimus- ja aivorunkoherätevastelöydösten sekä neurologisen kehityksen välisiä yhteyksiä. Tämän tutkimuksen mukaan kohdunsisäinen tulehdus ja istukan vajaatoiminta yhtä aikaa esiintyessään ovat poikkeavan neurologisen kehityksen itsenäisiä riskitekijöitä lapsilla 2 vuoden korjatussa iässä tutkittuna. Valkoisen aivoaineen vaurio edelleen lisäsi näiden lasten huonon neurologisen kehityksen ennustetta. Raskauden kestosta riippumatta, sikiön tulehdusvastetta kuvaavat napaveren akuutin vaiheen tulehdusvälittäjäaineet (IL-1α, IL-1β, IL-6, IL-8, TNF- α) eivät vaikuttaneet lapsen neurologiseen kehitykseen. Sen sijaan, CP-lasten napaverestä löytyi erityinen joukko ei-akuutin vaiheen välittäjäaineita. Nämä valkuaisaineet erosivat toisistaan täysiaikaisena ja ennenaikaisena syntyneillä CP-lapsilla. Raskauden- ja syntymänaikaiset verenkierron häiriöt vaikuttivat hyvin ennenaikaisena syntyneiden lasten myöhempään kehitykseen. Vaikeassa istukan vajaatoiminassa sikiön sydämen toiminnan heikkeneminen liittyi lapsen suboptimaaliin neurologiseen kehitykseen 1 vuoden korjatussa iässä tutkittuna. Lisäksi useat syntymänjälkeiset keuhkojen ja verenkierron tilaa kuvaavat kliiniset tekijät liittyivät lapsen poikkeavaan neurologiseen kehitykseen 2 vuoden korjatussa iässä tutkittuna. Tutkimuksemme mukaan, veden diffuusiota määrällisesti kuvaava diffuusiokerroin, ADC, aivosillasta mitattuna, liittyi impulssien johtumisnopeutueen kuuloradastossa. Lisäksi korkea ADC-arvo aivojen sepelviuhkassa liittyi karkean motoriikan ja silmä-käsi-yhteistyötaitojen huonoon kehitykseen 2 vuoden korjatussa iässä tutkittuna. Sekä raskauden- että syntymänaikaiset tekijät vaikuttavat hyvin ennenaikaisena syntyneiden lasten myöhempään kehitykseen. Yksittäinen sikiön tulehdusvaste ei ennakoi lapsen neurologista kehitystä. Tiettyjen aivoalueiden diffuusiokuvantamislöydökset ennustavat lapsen poikkeavaa neurologista kehitystä

CONTEXTE : les récepteurs activés par les proliférateurs des peroxysomes (PPAR) sont des membres de la superfamille des récepteurs nucléaires qui agissent en tant que facteurs de transcription activés par des ligands. Le PPARgamma joue un rôle essentiel dans la différenciation des adipocytes, le métabolisme des lipides et le développement du placenta. Les phtalates sont des contaminants environnementaux couramment utilisés comme plastifiants dans les produits à base de polychlorure de vinyle (PVC). Récemment, l'exposition de la femme enceinte aux phtalates, qui sont des ligands potentiels de PPARgamma, a été associée à de la prématurité, à des petit poids de naissance et à des interruptions de grossesse. Par ailleurs, des données récentes suggèrent que certaines mutations rares du domaine de liaison du ligand de PPARgamma (LBD) responsables de la lipodystrophie (FPLD3) seraient associées à des complications de la grossesse. OBJECTIFS : notre objectif général était d'évaluer l'activité et le rôle du PPARgamma placentaire durant la grossesse, et en particulier l'impact des phtalates et d'une mutation de PPARgamma associée à FPLD3 (E352Q) dans la différenciation et la fonction des trophoblastes humains in vitro. METHODES : dans ce but, nous avons : 1 / construit des plasmides rapporteurs (PPRE-H2B-eGFP et PPRE-pNL1.3 [secNluc]) pour quantifier l'activité de PPARgamma in vitro ; 2 / étudié l'action du MEHP (mono-2-éthylhexyl-phtalate) sur l'activité de PPARgamma et la différenciation des cytotrophoblastes villeux humains (CTVs) en utilisant des techniques d'immunofluorescence, de mesure de l'activité de PPARgamma, de dosage d'hCG, de western blot et d'analyse lipidomique ; 3 / étudié l'impact de la mutation de PPARgamma (E352Q) sur l'activité de PPARgamma en utilisant un lignée cellulaire NIH/3T3sur la différenciation in vitro des CTVs par analyse fonctionnelle après inactivation avec un siRNA et restitution de l'activité de PPARgamma « wild type » et de PPARgamma muté. RÉSULTATS : les constructions plasmidiques rapporteurs ont permis de quantifier l'activité de PPARgamma dans différents types cellulaires et conditions expérimentales. De plus, nous avons montré que des doses non toxiques de 0,1 µM et 1 µM de MEHP inhibaient significativement l'activité de PPARgamma et la différenciation des CTVs par rapport aux témoins, alors qu'étonnamment, 10 µM avait l'effet opposé. Par ailleurs, l'exposition de CTVs au MEHP inhibe la production d'hCG, altère de manière significative la composition lipidique trophoblastique perturbe sur la voie des MAPK (seul 10 µM de MEHP augmente la pERK alors que 0,1 ,1 et 10 µM diminuent les niveaux de protéine pJNK). Enfin, la mutation E352Q - associée à une grossesse pathologique a non seulement diminué l'activité de PPARgamma, mais également altéré la formation in vitro de syncytiotrophoblastes par fusion des CTVs primaires. CONCLUSION : des études de KO réalisées sur des souris ont montré l'importance de PPARgamma pour le développement du placenta et l'issue de la gestation. En utilisant deux nouveaux systèmes rapporteurs combinés avec un modèle in vitro de différenciation de CTVs, nous avons montré que le MEHP et la mutation E352Q perturbent l'activité de PPARgamma et la physiologie du trophoblaste humain ce qui pourraient expliquer les complications de la grossesse observées in vivo
BACKGROUND: The peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily that act as ligand-activated transcription factors. PPARgamma plays critical roles in adipocyte differentiation, lipid metabolism and placental development. Phthalates are environmental contaminants commonly used as plasticizers in polyvinyl chloride (PVC) products. Recently, exposure to phthalates, which are potential PPARgamma ligands, has been associated with preterm birth, low birth-weight, and pregnancy loss. On the other hand, there is emerging evidence that some rare mutations in PPARgamma ligand binding domain (LBD) responsible of human lipodystrophy (FPLD3), might be associated with pregnancy complications. OBJECTIVES: Our general goal was to assess placental PPARgamma activity and role during pregnancy and in particular the impact of phthalates and of a FPLD3-associated mutation of PPARgamma (E352Q) in trophoblast differentiation and functions in vitro. METHODS: In this purpose we have: 1/ constructed reporter plasmids (PPRE-H2B-eGFP & PPRE-pNL1.3[secNluc]) to monitor PPARgamma activity in vitro; 2/ investigated the action of MEHP (mono-2-ethylhexyl-phthalate) on PPARgamma activity and differentiation of primary human villous cytotrophoblasts (VCTs) by using immunofluorescence, PPARgamma activity and hCG assays, western blotting and lipidomics analyses and; 3/ studied the impact of the mutated-PPARgamma (E352Q) on PPARgamma activity in NIH/3T3-cell line, and on VCT differentiation through functional analysis (fusion index) using siRNA knockdown and functional restitution of PPARgamma and mutated PPARgamma in in vitro models. RESULTS: Constructed reporter plasmids allowed us to quantify PPARgamma activity in different cell types and experimental conditions. Furthermore, we showed that non-toxic doses of 0.1 µM and 1 µM MEHP significantly decreased PPARgamma activity and VCT differentiation compared to controls, while, surprisingly, 10 µM had the opposite effect. Also, MEHP exposure inhibited hCG production, significantly altered trophoblastic lipid composition and had significant effects on the MAPK pathway: only 10 µM MEHP increased pERK, whereas 0.1, 1 and 10 µM decreased pJNK protein levels. Finally, the E352Q mutation - associated with pregnancy complication - not only decreased PPARgamma activity, but also altered the in vitro formation of syncytiotrophoblasts by fusion of primary VCTs. CONCLUSION: PPARgamma KO studies in mice showed the importance of PPARgamma for placental development and gestation outcome. Using two novel PPRE reporter systems combined with in vitro model of VCT differentiation, we showed that MEHP and the E352Q mutation impact PPARgamma activity and disrupt human trophoblast physiology that, which could explain the pregnancy complications observed in vivo

This study is designed to investigate the nature of pathologically significant placentas and their corresponding fetal and neonatal outcomes in term infants. We aim to examine the correlation between specific placental pathologies and neonatal clinical conditions, including brain injury, requiring admission to a neonatal care unit and subsequent follow-up in our High Risk Newborn Follow-up Program (HRFU). A retrospective cohort study was conducted through review of maternal and neonatal reports. Overall 48 neonates had placentas submitted for examination. Sixty-one percent of placentas in the HRFU group and 62% of placentas in the non-HRFU group had findings consistent with ischemic changes, meconium staining and calcifications. Three infants had hypoxic ischemic encephalopathy. This study found no difference in placental pathology between non-HRFU infants and infants enrolled in the HRFU Program. This raises questions and warrants further study on the efficacy for placental submission as a predictive measure for neonatal outcomes.

此論文包括多個前瞻性橫斷面研究探討甲狀腺臨床功能正常之香港本地孕婦患上碘缺乏病的發生率，及孕婦碘攝取量，母體甲狀腺功能，胎兒甲狀腺功能，胎盤之轉甲狀腺素蛋白及鈉碘轉運體之表達水平在缺碘孕婦及碘充足孕婦之間的分別。研究包括患孕期併發症之孕婦，如妊娠糖尿病，子癎前期，單絨毛膜雙羊膜雙胞胎。
甲狀腺功能正常及正常或有併發症之孕婦獲邀參與本研究尿液碘含量是用作斷定孕婦的碘營養狀況。每日碘攝取量以一份飲食頻率問卷作估計。臍帶血及胎盤樣本用作檢驗胎兒甲狀腺功能和胎盤之轉甲狀腺素蛋白及鈉碘轉運體之表達水平。研究更包括懷有併發症之孕婦會跟正常孕婦之比較。
以世界衛生組織訂立之尿液碘含量準則，75.2%孕婦患碘缺乏。她們有較高的甲狀腺球蛋白、較高機率有甲狀腺球蛋白>13ug/L及較低的甲狀腺素，此結果均反映碘缺乏症的存在。孕婦和胎兒的甲狀腺功能關係在碘缺乏和碘足夠的情況下有不同的模式，但胎盤轉甲狀腺素蛋白及鈉碘轉運體之表達水平無分別。
有妊娠糖尿病之孕婦誕下較重之嬰兒，但母體及胎兒甲狀腺功能，胎盤轉甲狀腺素蛋白及鈉碘轉運體之表達水平沒有分別。但孕婦和胎兒的甲狀腺功能關係有所不同。
患有子癎前期之孕婦有較短的妊娠期、較低的胎盤鈉碘轉運體之表達水平、較輕的嬰兒體重、較輕的胎盤重量、嬰兒有較少的甲狀腺素及血清轉甲狀腺素蛋白水平。兩組孕婦亦擁有不同模式的孕婦和胎兒的甲狀腺功能，及胎盤鈉碘轉運體之表達水平關係。
懷有雙胞胎的孕婦有較高的每日碘攝取量及產前補充劑之使用次數，和較低的血清轉甲狀腺素蛋白水平。雙胞胎之間的胎兒甲狀腺功能沒有分別，但較輕的雙胞胎有較輕的體重，和較高的臍帶靜脈二氧化碳分壓水平。跟單胞胎相比，雙胞胎有較輕的出生體重及較少的血清轉甲狀腺素蛋白水平，但有較高的胎盤鈉碘轉運體之表達水平。兩組雙胞胎擁有不同模式的胎兒的甲狀腺功能，及胎盤鈉碘轉運體之表達水平關係。
不同模式的關係及胎盤鈉碘轉運體之表達水平反映出胎盤適應過程，這意味著成功的胎盤適應以維持胎兒正常的甲狀腺功能，從而保持胎兒正常發育及成熟過程中擔任著重要的角色，而最後令有孕期併發症之孕婦跟正常孕婦有近似的懷孕結果。
This thesis consists of a number of prospective cross-sectional studies to examine the incidence of iodine deficiency in local euthyroid gravidae, and its relationship with maternal iodine intake, and maternal and fetal thyroid function in iodine deficient and sufficient gravidae. In addition, the study also examined placental transthyretin (TTR) and sodium-iodide symporter (NIS) expression in normal and complicated pregnancies, including gestational diabetes mellitus (GDM), pre-eclampsia (PET) and monochorionic diamniotic (MCDA) twins.
Clinically euthyroid gravidae carrying normal or complicated pregnancies were recruited for the assessment of maternal thyroid function and iodine status as reflected in urinary iodine excretion. A food frequency questionnaire was used to estimate iodine intake. Umbilical cord blood and placenta were collected at delivery to determine fetal thyroid function and placental TTR and NIS expression. For gravidae with complicated pregnancies, matched controls were identified and recruited for comparison.
According to the World Health Organization urinary iodine concentration criterion, 75.2% gravidae were identified as iodine deficient. Presence of iodine deficiency was supported by the significantly higher maternal thyroglobulin level and incidence of maternal thyroglobulin>13ug/L, together with lower fetal free thyroxine (fT4) level, in the deficient group. Different patterns of correlation in maternal and fetal thyroid function were found between iodine deficient and sufficient gravidae, but no difference in placental TTR and NIS expression was found.
Gravidae with GDM delivered infants with significantly higher birth weight, but no difference in maternal and fetal thyroid function, or placental expression of TTR and NIS was found between the GDM and control groups. Nevertheless, there were different patterns of correlation in maternal and fetal thyroid function between GDM and control gravidae.
Compared with the normal group, the PET group had significantly shorter gestation, lower placental NIS protein expression, birth weight, placental weight, and fetal fT4 and serum TTR levels. Different patterns of correlation in maternal and fetal thyroid function, and placental NIS expression, were found between PET and control gravidae.
Compared with gravidae carrying singleton pregnancies, gravidae carrying twins had significantly higher daily iodine intake and frequency of supplement use, but lower serum TTR level. No difference in fetal thyroid function was found between the heavi
Ng, Yu Tai Russell.
Thesis Ph.D. Chinese University of Hong Kong 2016.
Includes bibliographical references (leaves ).
Abstracts also in Chinese.
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The invasion of trophoblast cells into the uterine wall is an essential component of normal human pregnancy. These trophoblast cells transform the uterine spiral arterioles into high-flow, low-resistance vessels that supply the placenta to support fetal growth and development. Inadequate trophoblast invasion and spiral arteriole remodelling may result in excessive placental pathology leading to pre-eclampsia and intra-uterine growth restriction (IUGR), which are major causes of maternal and fetal morbidity and mortality. These pregnancy complications have also been linked to an increased presence of pro-inflammatory cytokine-secreting (activated) macrophages at the fetal-maternal interface. In particular, increased production of tumour necrosis factor-alpha (TNF) by activated macrophages has been implicated as a causative factor mediating various pregnancy complications. Results from this thesis showed that macrophage-derived TNF decreased the invasiveness of trophoblast cells, primarily by affecting the urokinase system of plasminogen activators, a network of proteases that promotes cellular invasion. TNF also stimulated the production of macrophage chemoattractants by trophoblast cells, providing a putative mechanism for the aberrant recruitment and localization of macrophages in complicated pregnancies. Administration of lipopolysaccharide (LPS), a potent stimulator of macrophage activation and TNF production, to pregnant rats resulted in IUGR and fetal death correlating with significant placental pathology, including displaced endovascular trophoblast cells and increased fibrinoid and macrophage accumulation at the fetal-maternal interface. The immunoregulatory cytokine interleukin-10, which inhibited TNF production from macrophages after LPS-exposure, completely prevented the adverse effects of TNF in vitro and in vivo. Collectively, these findings show that the aberrant presence and localization of TNF-secreting macrophages may be involved in the etiology and pathophysiology of various pregnancy-related complications.
Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2008-09-29 16:32:00.845

Prenatal exposure to sex hormones has profound effects on neurodevelopment with lifelong implications for mental health. Fetal exposure to aberrant levels of sex hormones alters sexual dimorphism (i.e. degree of feminization or masculinization; sex differences in brain and behavior) and may contribute to the differential susceptibility of males and females to psychiatric risk and neurodevelopmental disorders, including autism. During fetal development, the in-utero environment is regulated by the placenta, a maternal-fetal endocrine structure that serves as a “gate-keeper” between the maternal and fetal circulatory systems. The placenta expresses high levels of aromatase, an enzyme that converts testosterone to estrogen, and it has been proposed that placental aromatase precludes the transfer of maternal testosterone to the fetus. However, this view does not account for individual differences in placental aromatase expression or maternal hormone levels that may account for altered neurobehavioral outcomes. Retinoic acid-related orphan receptor-alpha (RORA) has been identified as a transcription factor that regulates aromatase and as an autism candidate gene – yet the role of RORA in the placenta as a regulator of the prenatal hormonal environment has yet to be determined. The research presented in this thesis aimed to evaluate 1) the relationship between maternal and neonatal hormone concentrations, 2) whether placental aromatase/RORA influences the relationship between maternal and neonatal hormones concentrations, 3) the relationship between maternal sex hormones during pregnancy and neurobehavioral outcomes in the offspring, and 4) the relationship between placental aromatase/RORA and neurobehavioral outcomes in the offspring. Chapters 1 and 2 of this thesis provide a review of the literature pertaining to the sources of and neurodevelopmental consequences of fetal exposure to hormones and the methods used to address our research questions. Chapters 3, 4, and 5 of this thesis used in vivo and in vitro methods to investigate the role of placental aromatase and RORA in regulating fetal exposure to maternal hormones. Results from these studies indicate that maternal testosterone is a strong predictor of neonatal testosterone levels at birth and that aromatase and RORA expression in the human placenta subtly influence the relationship between maternal and neonatal testosterone and estradiol in a sex-dependent manner. Results from our studies using an in vitro approach call into question the widely proposed role of placental aromatase in converting maternal testosterone intro estradiol. Chapters 6 and 7 of this thesis aimed to determine whether variability in maternal testosterone and placental aromatase/RORA expression was associated with increased neurodevelopmental risk as a result of elevated fetal hormone exposure. For the first time in the literature, we report a direct association between elevated maternal testosterone and poorer childhood neurodevelopmental outcome in a sex-dependent manner. We also report that the effects of placental aromatase and RORA expression on childhood outcomes vary depending on the neurobehavioral domain being assessed. Taken together, these studies support the notion that fetal exposure to sex hormones, especially those of maternal origin, can affect neonatal hormone production as well as long-term child neurobehavior. The specific mechanisms by which the placenta regulates fetal exposure require further investigation.

Σκοπός: Οι μορφές κληρονομικής θρομβοφιλίας έχουν θεωρηθεί σαν μία κατάσταση με πιθανά αυξημένη ευαισθησία για δυσμενή έκβαση της εγκυμοσύνης. Σκοπός της παρούσας μελέτης είναι η διερεύνηση της επίδρασης των κληρονομικών θρομβοφιλικών παραγόντων στην έκβαση της εγκυμοσύνης σε τυχαίο δείγμα εγκύων γυναικών της Νοτιο-Δυτικής Ελλάδος. Υλικό-Μέθοδος: 396 γυναίκες με αυτόματη έναρξη της εγκυμοσύνης μελετήθηκαν για τις πιο συχνές θρομβοφιλικές μεταλλάξεις (παράγοντας V Leiden, G20210A πολυμορφισμός του παράγοντα II, C677T πολυμορφισμός του MTHFR γονιδίου) και παρακολουθήθηκαν για δυσμενή έκβαση της εγκυμοσύνης. Οι συγκρίσεις μεταξύ των ομάδων πραγματοποιήθηκαν με τη δοκιμασία Pearson’s x2 και υπολογίστηκε το Odds Ratio. Αποτέλεσμα: Οι θρομβοφιλικοί γονότυποι ήταν σημαντικά υψηλότεροι στις γυναίκες με αποκόλληση πλακούντα. Στις γυναίκες που ήταν ετεροζυγώτες στον παράγοντα V Leiden ο κίνδυνος για αποκόλληση πλακούντα αυξανόταν κατά 6.58 φορές, ενώ στις γυναίκες που ήταν ομοζυγώτες στον C677T πολυμορφισμό του MTHFR γονιδίου ο κίνδυνος αυξανόταν κατά 4.3 φορές. Οι γυναίκες με κληρονομική θρομβοφιλία και επιπλοκές σε προηγούμενες εγκυμοσύνες, παρουσίαζαν σημαντικό κίνδυνο για επιπλοκές σε επόμενη εγκυμοσύνη (p<0.05). Συμπέρασμα: Οι γυναίκες με αποκόλληση πλακούντα θα πρέπει να ελέγχονται για κληρονομική θρομβοφιλία και να εξετάζεται η λήψη προφυλακτικής αντιπηκτικής αγωγής. Οι γυναίκες που είναι ομοζυγώτες στον C677T πολυμορφισμό του MTHFR γονιδίου θα πρέπει να έχουν εκτεταμένο εργαστηριακό έλεγχο και να λαμβάνουν τα ανάλογα σκευάσματα.
Objective: Inherited thrombophilias have been suggested as a possible condition of increased susceptibility to adverse pregnancy outcomes. The purpose of the present study was to investigate the impact of inherited thrombophilic factors in the gestational outcome of unselected pregnant women from South-Western Greece. Material-Method: 396 women with spontaneous pregnancy were investigated for the commonest thrombophilic mutations (Factor V Leiden, prothrombin G20210A, MTHFR C677T) and followed for adverse pregnancy outcomes. Comparisons between groups were performed by Pearson’s chi-square test and odd ratios were calculated. Result: Thrombophilic genotypes were significantly higher in women with placental abruption. Heterozygocity for Factor V Leiden increased 6.58 times the risk for placental abruption while homozygocity for C677T MTHFR mutation increased the risk 4.3 times. Women with inherited thrombophilia and previous obstetric complications were at significant risk for complications in a subsequent pregnancy (p<0.05). Conclusion: Women with placental abruption should be screened for inherited thrombophilia and considered for prophylactic anticoagulation. Women homozygous for C677T MTHFR mutation should have an extensive work up and receive supplements accordingly.

L’infection génitale par le Virus du Papillome Humain (VPH) est l’infection transmissible sexuellement la plus fréquente. Sa prévalence la plus élevée est retrouvée chez les femmes en âge de procréer. Bien que la littérature expérimentale s’accorde sur la plausibilité biologique de l’effet du VPH sur les issues négatives de grossesse, les résultats des études observationnelles sont équivoques. Parmi ces issues négatives figure l’accouchement prématuré qui reste une cause majeure de mortalité périnatale et de morbidité à vie dans le monde. La présente thèse avait alors pour but de faire la lumière sur la qualité de la littérature actuelle sur les issues négatives de grossesse en lien avec le VPH en général et d’approfondir l’association entre le VPH et l’accouchement prématuré en particulier. À cette fin, trois objectifs de recherche étaient visés, à savoir: 1) évaluer systématiquement l’ampleur de l’association entre l’infection VPH et les issues négatives de grossesse dans la littérature et la qualité des évidences sur ces relations, 2) estimer l’association entre l’infection VPH pendant la grossesse et l’accouchement prématuré et 3) identifier les déterminants de la transmission du VPH dans le placenta chez les femmes infectées par le VPH au niveau vaginal. Trois analyses ont été menées pour répondre à chacun des objectifs. D’abord, nous avons effectué une revue systématique et des méta-analyses pour chacune des issues négatives de grossesse suivantes: avortement spontané, rupture prématurée et/ou préterme et des membranes, accouchement prématuré, faible poids de naissance, retard de croissance intra-utérine, troubles hypertensifs gestationnels et mortinaissance. Ensuite, en utilisant les données des femmes éligibles de la cohorte prospective HERITAGE (n=899), nous avons estimé l’association entre l’infection VPH (pendant la grossesse et dans le placenta) et l’accouchement prématuré. Dans un modèle de régression logistique, un ajustement pour la confusion a été assuré par pondération par l’inverse de probabilité de l’infection VPH au premier trimestre en fonction des caractéristiques maternelles. Enfin, l’analyse des déterminants du VPH dans le placenta a été réalisée sur l’échantillon de la cohorte de femmes positives au VPH au premier trimestre de grossesse (n=354) en utilisant un modèle d’équations d’estimation généralisée. La revue systématique et les méta-analyses ont montré que l’infection VPH est associée à plusieurs issues négatives de grossesse dont l’accouchement prématuré. Cependant, ces résultats doivent être interprétés avec prudence, compte tenu des limites dans certaines études en raison d’erreur de mesure de l’exposition au VPH, d’une détection du VPH en dehors de la période de grossesse, et d’un contrôle insuffisant pour la confusion. Les résultats de notre étude de cohorte prospective ont montré que la persistance des VPH16/18 pendant la grossesse et la présence du VPH dans le placenta sont associées à l’accouchement prématuré avec un odds ratio ajusté (aOR) de 3,72 (IC 95% 1,47-9,39) et 2,53 (IC 95% 1,06- 6,03) respectivement. Cet effet est indépendant des antécédents de traitement de dysplasies cervicales. Par ailleurs, la présence du VPH dans le placenta est associée à l’origine ethnique autre que blanc (aOR 1,78; IC 95% 1,08-2,96), aux anomalies cervicales (aOR 1,92; IC 95% 1,14-3,24), à l’infection génitale ou urinaire (aOR 2,32; IC 95% 1,15-4,68), à la coinfection VPH au 1er trimestre (aOR 2,56; IC 95% 1,72-3,83), à la persistance d’un VPH à haut risque autre que les génotypes 16/18 (2,31; IC 95% 1,20-4,45) et à la persistance des VPH-16/18 pendant la grossesse (aOR 4,55; IC 95% 2,40-8,66). Dans l’ensemble, les résultats de cette thèse apportent de nouvelles connaissances sur l’infection VPH vaginale pendant la grossesse et dans le placenta. L’association entre l’accouchement prématuré et la persistance du VPH-16/18 en cours de grossesse ou l’infection VPH dans le placenta indique qu’un certain nombre d’accouchements prématurés, jusque-là inexpliqués, pourraient être en lien avec le VPH. Cet effet direct de l’infection VPH sur l’accouchement prématuré vient s’ajouter à celui, déjà montré, du traitement cervical des lésions dysplasiques. Le VPH placentaire est associé aux marqueurs d’une réponse immunitaire inadéquate contre le VPH vaginal. Nos résultats plaident en faveur de la couverture vaccinale optimale contre le VPH dans le but d’alléger le fardeau des naissances prématurées.
Human Papillomavirus (HPV) genital infection is the most common sexually transmitted infection. Its highest prevalence is found in women of childbearing age. Although experimental studies agree on the biological plausibility of detrimental effect of HPV on pregnancy outcomes, observational studies yielded contradictory findings. Among these negative outcomes there is preterm delivery, which remains a major cause of perinatal mortality and lifelong morbidity worldwide. Therefore, this thesis aimed to shed light on the quality of the current literature on negative outcomes related to HPV in general and specifically to further investigate the association between HPV and preterm birth. We targeted three research objectives: 1) systematic assessment of the association between HPV infection and negative pregnancy outcomes in the literature and the quality of the evidence on these relationships, 2) estimate the association between HPV infection during pregnancy and preterm delivery; and 3) to identify the determinants of HPV transmission in the placenta in women infected with in the first trimester. Three analyzes were carried out to meet each of the objectives. We performed a systematic review and meta-analyzes for each of the following negative pregnancy outcomes: spontaneous abortion, premature and / or preterm rupture and membranes, preterm birth, low birth weight, intra-uterine growth retardation, pregnancy induced hypertensive disorders and stillbirth. Using data from eligible women in the HERITAGE prospective cohort (n = 899), we assessed the association between HPV infection (during pregnancy and in the placenta) and preterm birth. In a logistic regression model, we adjusted for confounding by inverse propensity treatment weighting of HPV infection in the first trimester based on maternal characteristics. Finally, the analysis of the determinants of HPV in the placenta was performed on the sample of the cohort of HPV positive women in the first trimester of pregnancy (n = 354) using a generalized estimation equations model. The systematic review and meta-analyzes showed that HPV infection is associated with several negative pregnancy outcomes including preterm birth. However, these results should be interpreted with caution, given the limitations in some studies regarding misclassification of HPV exposure, inappropriate HPV time-point detection, and insufficient control for confusion. Our prospective cohort study showed that the persistence of HPV16/18 during pregnancy and the presence of any HPV in the placenta are associated with preterm birth with an adjusted odds ratio (aOR) of 3.72 (CI 95 % 1.47-9.39) and 2.53 (95% CI 1.06-6.03) respectively. These findings are independent of the history of cervical dysplasia treatment. In addition, the presence of any HPV in the placenta is associated with ethnic origin other than white (aOR 1.78; 95% CI 1.08-2.96), cervical abnormalities (aOR 1.92; 95% CI 1.14-3.24), genital or urinary infection (aOR 2.32; 95% CI 1.15-4.68), HPV coinfection in the 1st trimester (aOR 2.56; 95% CI 1.72-3.83), persistence of high-risk HPV other than genotypes 16/18 (2.31; 95% CI 1.20-4.45) and persistence of HPV-16/18 during pregnancy (aOR 4.55; 95% CI 2.40-8.66). Overall, our findings provide new evidence on vaginal HPV infection during pregnancy and in the placenta. The association between preterm birth and persistence of HPV-16/18 during pregnancy or any HPV infection in the placenta indicates that a number of unexplained preterm deliveries may be related to HPV. This direct effect of HPV infection on preterm birth is in addition to that already shown of cervical treatment of dysplastic lesions. Placental HPV is associated with markers of an inadequate immune response against vaginal HPV. Our results argue in favor of an increase in vaccine coverage against HPV in order to reduce the burden of preterm births.