Increasing maternal obesity is associated with alterations in both maternal and neonatal thyroid hormone levels

Maternal pre-pregnancy obesity modifies the association between first-trimester thyroid hormone sensitivity and gestational Diabetes Mellitus: a retrospective study from Northern China

BACKGROUND

Contradictory relationships have been observed between thyroid function and gestational diabetes mellitus (GDM). Previous studies have indicated that pre-pregnancy BMI (pBMI) could modify their relationships. Few studies have illustrated the role of thyroid hormone sensitivity on GDM. We aimed to explore the effect of pre-pregnancy obesity on the association between early pregnancy thyroid hormone sensitivity and GDM in euthyroid pregnant women.

METHODS

This study included 1310 women with singleton gestation. Subjects were classified into pre-pregnancy obese and non-obese subgroups by pBMI levels with a cutoff of 25 kg/m2. Sensitivity to thyroid hormone was evaluated by Thyroid Feedback Quartile-Based Index (TFQI), Chinese-referenced parametric TFQI (PTFQI), TSH Index (TSHI) and Thyrotrophic T4 Resistance Index (TT4RI). The associations between these composite indices and GDM were analyzed using multivariate regression models in the two subgroups, respectively.

RESULTS

In pre-pregnancy non-obese group, early pregnancy TFQI, PTFQI, TSHI and TT4RI levels were higher in subjects with incident GDM compared to those without GDM (all P < 0.05). By contrast, obese women with GDM exhibited lower levels of those indices (all P < 0.05). The occurrence of GDM were increased with rising TFQI, PTFQI, TSHI and TT4RI quartiles in non-obese women ( all P for trend < 0.05), while exhibited decreased trend across quartiles of those indices in obese women (all P for trend < 0.05). Further logistic analysis indicated contrary relationships between thyroid hormone sensitivity and the occurrence of GDM in the two groups, respectively. The OR of the fourth versus the first quartile of TFQI for GDM was 1.981 (95% CI 1.224, 3.207) in pre-pregnancy non-obese group, while was 0.131 (95% CI 0.036, 0.472) in pre-pregnancy obese group. PTFQI and TSHI yielded similar results.

CONCLUSIONS

The association between maternal sensitivity to thyroid hormones during early gestation and the occurrence of GDM was modified by pre-pregnancy obesity.

Maternal diet alters long-term innate immune cell memory in fetal and juvenile hematopoietic stem and progenitor cells in nonhuman primate offspring

Maternal overnutrition increases inflammatory and metabolic disease risk in postnatal offspring. This constitutes a major public health concern due to increasing prevalence of these diseases, yet mechanisms remain unclear. Here, using nonhuman primate models, we show that maternal Western-style diet (mWSD) exposure is associated with persistent pro-inflammatory phenotypes at the transcriptional, metabolic, and functional levels in bone marrow-derived macrophages (BMDMs) from 3-year-old juvenile offspring and in hematopoietic stem and progenitor cells (HSPCs) from fetal and juvenile bone marrow and fetal liver. mWSD exposure is also associated with increased oleic acid in fetal and juvenile bone marrow and fetal liver. Assay for transposase-accessible chromatin with sequencing (ATAC-seq) profiling of HSPCs and BMDMs from mWSD-exposed juveniles supports a model in which HSPCs transmit pro-inflammatory memory to myeloid cells beginning in utero. These findings show that maternal diet alters long-term immune cell developmental programming in HSPCs with proposed consequences for chronic diseases featuring altered immune/inflammatory activation across the lifespan.

SERUM GLP-2 is Increased in Association with Excess Gestational Weight Gain

OBJECTIVE

Obesity in pregnancy bears unique maternal and fetal risks. Obesity has also been associated with chronic inflammation, including elevated serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Higher serum lipopolysaccharide (LPS) levels have been implicated in driving this inflammation, a phenomenon called metabolic endotoxemia (ME). GLP-2, a proglucagon-derived peptide, is believed to be integral in maintaining the integrity of the intestine in the face of LPS-mediated endotoxemia. We hypothesized that obesity and/or excess weight gain in pregnancy would be associated with an increase in maternal and neonatal markers of ME, as well as GLP-2.

STUDY DESIGN

Paired maternal and neonatal (cord blood) serum samples (n = 159) were obtained from our pregnancy biobank repository. Serum levels of LPS, endotoxin core antibody-immunoglobulin M (EndoCAb-IgM), and GLP-2 were measured by ELISA. IL-6 and TNF-α were measured using a Milliplex assay. Results were stratified by maternal body mass index (BMI), maternal diabetes, and gestational weight gain (GWG).

RESULTS

Maternal IL-6 is significantly decreased in the obese, diabetic cohort compared with the nonobese, nondiabetic cohorts (95.28 vs. 99.48 pg/mL, p = 0.047), whereas GLP-2 is significantly increased (1.92 vs. 2.89 ng/mL, p = 0.026). Neonatal TNF-α is significantly decreased in the obese cohort compared with the nonobese cohort (12.43 vs. 13.93 pg/mL, p = 0.044). Maternal GLP-2 is significantly increased in women with excess GWG compared with those with normal GWG (2.27 vs. 1.48 ng/mL, p = 0.014). We further found that neonatal IL-6 and TNF-α are negatively correlated with maternal BMI (-0.186, p = 0.036 and -0.179, p = 0.044, respectively) and that maternal and neonatal IL-6 showed a positive correlation (0.348, p < 0.001).

CONCLUSION

Although we observed altered levels of markers of inflammation (IL-6 and TNF-α) with maternal obesity and diabetes, no changes in LPS or endoCAb-IgM were observed. We hypothesize that the increased GLP-2 levels in maternal serum in association with excess GWG may protect against ME in pregnancy.

KEY POINTS

· Maternal serum levels of GLP-2, a proglucagon-derived peptide, are increased in obese, diabetic gravidae.. · Maternal serum GLP-2 levels are also increased in association with excess gestational weight gain compared with normal gestational weight gain.. · GLP-2 may be increased in association with obesity and weight gain to protect against metabolic endotoxemia in pregnancy..

Thyroid hormones and carnitine in the second trimester negatively affect neonate birth weight: A prospective cohort study

BACKGROUND

Maternal thyroid hormones and carnitine are reported to affect neonate birth weight during the second trimester, which is one of the most important markers for fetal growth and perinatal mortality and morbidity. Nevertheless, the effect of thyroid hormone and carnitine in the second trimester on birth weight has yet to be understood.

METHOD

This was a prospective cohort study with 844 subjects enrolled during the first trimester. Thyroid hormones, free carnitine (C0), neonate birth weight, as well as other related clinical and metabolic data were collected and assessed.

RESULTS

Pre-pregnancy weight and body mass index (BMI) as well as neonate birth weight were significantly different among different free thyroxine (FT4) level groups. Maternal weight gain and neonate birth weight varied significantly when grouped by different thyroid-stimulating hormone (TSH) levels. There was a significantly positive correlation between C0 and TSH (r = 0.31), free triiodothyronine (FT3) (r = 0.37), and FT4 (r = 0.59) (all P < 0.001). In addition, a significantly negative influence was found between birth weight and TSH (r = -0.48, P = 0.028), so as C0 (r = -0.55, P < 0.001) and FT4 (r = -0.64, P < 0.001). Further assessment detected a stronger combined effect of C0 and FT4 (P < 0.001) and of C0 and FT3 (P = 0.022) on birth weight.

CONCLUSION

Maternal C0 and thyroid hormones are of great importance in neonate birth weight, and routine examination of C0 and thyroid hormones during the second trimester has a positive effect on the intervention of birth weight.

Effect of Maternal Triclosan Exposure on Neonatal Thyroid-Stimulating Hormone Levels: A Cross-Sectional Study

Objective

This study is aimed at assessing the relationship between maternal urinary triclosan (uTCS) exposure and the thyroid-stimulating hormone (TSH) level of infant cord blood.

Methods

This cross-sectional study was carried out in 2019-2020 in Isfahan, Iran, and 99 pregnant women participated in the study. Urine samples were collected after the 28th week of pregnancy, and the concentration of TCS was measured using GC/MS. The cord blood levels of TSH (CBL-TSH) were measured. The association between uTCS and CBL-TSH was examined based on the general linear model.

Results

TCS was detected (≥0.01 ng/mL) in 100% of the urine samples, with the interquartile range (25%-75%) of uTCS levels 0.6-6.23 μg/g Cr. uTCS was not associated with CBL-TSH after adjustment for covariates. A significant relationship was observed between CBL-TSH of neonates born to mothers who had given birth only once compared to mothers who had given birth twice or more times.

Conclusions

Maternal exposure to TCS did not affect the infant CBL-TSH. However, the high concentrations of TCS in maternal urinary samples indicate the necessity of more precise regulations to decrease the use of this chemical in the industry and increase public awareness about using TCS-free compounds.

Increased maternal leptin levels may be an indicator of subclinical hypothyroidism in a newborn

Background

Several factors may influence newborn thyroid-stimulating hormone (TSH) concentrations and cause subclinical hypothyroidism in a newborn. A sufficient level of leptin signalling is needed for the normal production of TSH and thyroid hormones by the thyroid gland. Our study aimed to investigate the correlation between maternal serum leptin concentration during the third trimester of pregnancy and newborn screening-TSH levels.

Methods

This prospective cross-sectional study was conducted in obstetrics and gynaecology clinics of a state hospital between June and August 2013. Maternal venous blood samples were collected from 270 healthy pregnant women in the third trimester just before delivery. Measurements of maternal fT3, fT4, TSH, anti-thyroid peroxidase (TPO), and anti-thyroglobulin (anti-Tg) antibodies from serum samples were performed by chemiluminescence immunoassay. Maternal serum leptin levels were determined by ELISA. Dried capillary blood spots were used to measure newborn TSH levels.

Results

Subjects were divided into two groups according to the neonatal TSH levels using a cut-point of 5.5 mIU/L. Median maternal serum leptin levels were significantly higher in newborns whose TSH levels were higher than >5.5 mIU/L [13.2 μg/L (1.3 - 46.5) vs 19.7 μg/L (2.4 - 48.5), p<0.05]. Serum leptin levels showed a negative correlation with maternal fT4 (r=0.32, p<0.05), fT3 (r=0.23, p<0.05), and a positive correlation with BMI (r=0.30, p<0.05).

Conclusions

Our results suggest that high leptin levels in the third trimester of pregnancy influence maternal thyroid functions and might cause an increase in newborn TSH levels. Detection of high maternal serum leptin levels may be a reason for subclinical hypothyroidism.

Maternal Obesity in Twin Pregnancy: The Role of Nutrition to Reduce Maternal and Fetal Complications

There are more and more obese mothers with twin gestations. For a long time before, the responses of lymphocytes and platelets in obese women can cause a low-grade inflammation. In addition, a proper control of gestational weight gain would improve the outcomes in mothers with high pre-gestational body mass index (BMI). In women with high pre-gestational BMI and twin pregnancy, our aims were to explore the biochemical and hematological parameters and to study the rate of obstetric adverse outcomes. This was an observational and retrospective study conducted in the Hospital Universitario La Paz (Madrid, Spain). We included 20 twin pregnancies as the lean group (BMI = 18.5–24.9 kg/m²), homogeneous in the maternal age and ethnicity, and having parity with other 20 twin pregnancies as the obese group (BMI ≥ 30 kg/m²). The maternal data and maternal, fetal, obstetric, and neonatal complications were collected from the medical records. In the first and third trimester of pregnancy, the biochemical and hematological parameters of the blood were assayed. In this cohort, gestational weight gain was significantly lower in the obese than lean group. In the first trimester, the hemoglobin levels in obese women (12.1 ± 0.8 g/dL) were lower than lean women (12.6 ± 0.7 g/dL; p-Value = 0.048). In addition, the tendency of glucose levels, TSH levels and platelets was to increase in obese compared to lean women. In the third trimester, the TSH levels were higher in obese (3.30 ± 1.60 mUI/L) than lean women (1.70 ± 1.00 mUI/L; p-Value = 0.009). Furthermore, there was a tendency for levels of platelets and lymphocytes to increase in obese compared to lean women. No significant differences were detected in the rate of maternal, fetal, obstetrical, and neonatal complications between the groups. The hemoglobin, platelets, lymphocytes and TSH levels need further investigation to understand potential subclinical inflammation in obese women. Furthermore, obese women with twin pregnancies should follow-up with a specialist nutritionist, to help them control their gestational weight gain with appropriate dietary measures.

Maternal and early life exposures and their potential to influence development of the microbiome

At the dawn of the twentieth century, the medical care of mothers and children was largely relegated to family members and informally trained birth attendants. As the industrial era progressed, early and key public health observations among women and children linked the persistence of adverse health outcomes to poverty and poor nutrition. In the time hence, numerous studies connecting genetics ("nature") to public health and epidemiologic data on the role of the environment ("nurture") have yielded insights into the importance of early life exposures in relation to the occurrence of common diseases, such as diabetes, allergic and atopic disease, cardiovascular disease, and obesity. As a result of these parallel efforts in science, medicine, and public health, the developing brain, immune system, and metabolic physiology are now recognized as being particularly vulnerable to poor nutrition and stressful environments from the start of pregnancy to 3 years of age. In particular, compelling evidence arising from a diverse array of studies across mammalian lineages suggest that modifications to our metagenome and/or microbiome occur following certain environmental exposures during pregnancy and lactation, which in turn render risk of childhood and adult diseases. In this review, we will consider the evidence suggesting that development of the offspring microbiome may be vulnerable to maternal exposures, including an analysis of the data regarding the presence or absence of a low-biomass intrauterine microbiome.

FT3/FT4 mediated the effect of pre-pregnancy body mass index or maternal weight gain during early pregnancy on gestational diabetes mellitus

OBJECTIVE

Maternal overweight or obesity during early pregnancy could increase the subsequent risk of gestational diabetes mellitus (GDM). However, whether these associations were mediated by thyroid hormones and their effect sizes were still unknown. This study aimed to identify the mediating effects of thyroid parameters between pre-pregnancy body mass index (BMI)/maternal weight gain during early pregnancy with subsequent risk of GDM.

METHODS

This prospective mother-infant cohort study was conducted from 2018 to 2019. A total of 2,772 singleton pregnant women were included for analysis. Questionnaire survey, anthropometric measures, and thyroid function testing were conducted in early pregnancy. Deiodinase activity was evaluated using free-triiodothyronine-to-free-thyroxine ratio (FT3/FT4). A standard 75 g oral glucose tolerance test was performed during 24-28 weeks of gestation to diagnose GDM. Mediation analysis was performed on PROCESS 3.5 to examine the mediating effects of thyroid parameters between pre-pregnancy BMI/maternal weight gain during early pregnancy and the subsequent GDM risk.

RESULTS

FT3/FT4 ratio was a significant mediator between pre-pregnancy BMI or maternal weight gain and GDM, accounting for 16.5% and 18.6% of total effects, respectively. FT3 also mediated the association of pre-pregnancy BMI with GDM, accounting for 3.3% of total effects. Thyroid-stimulating hormone suppressed the effects of pre-pregnancy BMI and maternal weight gain on GDM risk, and the proportions of total effects were 2.4% and 6.4%, respectively.

CONCLUSIONS

Deiodinase activity, as indicated by FT3/FT4 ratio, was the strongest mediator among thyroid parameters between pre-pregnancy BMI/maternal early weight gain and GDM.

Maternal adiposity, smoking, and thyroid function in early pregnancy

OBJECTIVE

A high activity of the deiodinase type 2 has been proposed in overweight, obese, and smoking pregnant women as reflected by a high triiodothyronine (T3)/thyroxine (T4) ratio. We speculated how maternal adiposity and smoking would associate with different thyroid function tests in the early pregnancy.

DESIGN

Cross-sectional study within the North Denmark Region Pregnancy Cohort.

METHODS

Maternal thyroid-stimulating hormone (TSH), total T4 (TT4), total T3 (TT3), free T4 (fT4), and free T3 (fT3) were measured in stored blood samples (median gestational week 10) by an automatic immunoassay. Results were linked to nationwide registers, and live-birth pregnancies were included. The associations between maternal adiposity (overweight or obese), smoking, and log-transformed TSH, fT3/fT4 ratio, and TT3/TT4 ratio were assessed using multivariate linear regression and reported as adjusted exponentiated β coefficient (aβ) with 95% CI. The adjusted model included maternal age, parity, origin, week of blood sampling, and diabetes.

RESULTS

Altogether 5529 pregnant women were included, and 40% were classified with adiposity, whereas 10% were smoking. Maternal adiposity was associated with higher TSH (aβ 1.13 (95% CI 1.08-1.20)), whereas maternal smoking was associated with lower TSH in the early pregnancy (0.875 (0.806-0.950)). Considering the T3/T4 ratio, both maternal adiposity (fT3/fT4 ratio: 1.06 (1.05-1.07); TT3/TT4 ratio: 1.07 (1.06-1.08)) and smoking (fT3/fT4 ratio: 1.07 (1.06-1.09); TT3/TT4 ratio: 1.10 (1.09-1.12)) were associated with a higher ratio.

CONCLUSIONS

In a large cohort of Danish pregnant women, adiposity and smoking showed opposite associations with maternal TSH. On the other hand, both conditions were associated with a higher T3/T4 ratio in early pregnancy, which may reflect altered deiodinase activity.

Perinatal effects of persistent organic pollutants on thyroid hormone concentration in placenta and breastmilk

Thyroid hormones (TH) are known to play a critical role in regulating many biological processes including growth and development, energy homeostasis, thermogenesis, lipolysis and metabolism of cholesterol. Severe TH deficiency especially during fetal development results in cretinism, but can also lead to an imbalance in metabolism with, among others, an alteration in body weight composition. Over the past two decades, increasing evidence has shown that certain persistent organic pollutants (POP) can interfere with the endocrine system. These POP referred to as "endocrine disrupting chemicals" are widely present in the environment and populations are exposed globally. Moreover, epidemiological studies have shown that a particularly sensitive period is the pre- and postnatal time. Indeed, perinatal exposure to such chemicals could lead to the onset diseases in later life. It is known, that, maternal thyroid hormones are transported by the placenta to the fetus from 6 weeks of gestation and it seems that during the first trimester, and part of the second, the fetus is entirely dependent on maternal TH supply for its development. Interferences in the TH-network as a consequence of the exposure to such pollutants could cause variations in TH concentration. Only small changes in maternal thyroid hormone levels in early stages of pregnancy can influence fetal neurological and cardiovascular development, as well as according to recent studies, have effect on childhood body composition. With this review, we will report the most recent and important studies concerning the association between thyroid hormone concentration and POP levels measured during the perinatal period. We will mostly focus on the data recently reported on placenta and breastmilk as main sources for understanding the potential consequences of exposure. The possible link between exposure to pollutants, TH dysregulation and possible adverse outcome will also be briefly discussed. From our literature search, several studies support the hypothesis that pre- and postnatal exposure to different pollutants might play a role in causing variation in thyroid hormone concentration. However, few research papers have so far studied the relationship linking exposure to pollutants, TH concentration and possible health consequences. Therefore, this review highlights the need for further research in this direction.

Assessing the Impact of Obesity on Pregnancy and Neonatal Outcomes among Saudi Women

Background: The rising prevalence of obesity has a significant impact on obstetrics practice regarding maternal and perinatal complications includes recurrent miscarriage, pregnancy-induced hypertension, preeclampsia, gestational diabetes, and prolonged labor. Objective: To assess the impact of obesity on pregnancy and neonatal outcomes among Saudi women. Methods: The study was conducted at King Abdul-Aziz Medical City, Jeddah. Design: A cross-sectional retrospective design. A total number of 186 participants were recruited from July to December 2018 according to eligibility criteria. The data were collected retrospectively by a review of the chart records of the labor and delivery department. Results: The mean (SD) age of participants was 31.94 (5.67) years old; two-thirds were in obesity class I. There was a significant association between obesity and pre-existing thyroid disease and induced hypertension class III. However, episiotomy showed that obesity class III was significantly different from obesity class II. Conclusion: This study concludes obesity affects the outcomes of pregnant Saudi associations between obesity and preeclampsia, perineal tears, and episiotomy variables, and other variables reflect no associations. Recommendations: Further studies are needed to generalize the results. This study endorses the pregnant women start the antenatal follow-up from 1st trimester so, the data will be available on the system for research.

Maternal thyroid disease and adiposity in mother and child

OBJECTIVE

Thyroid hormones are crucial developmental factors, and thyroid disease in pregnant women is a concern. Overweight and obesity are also important health concerns, and we hypothesized that in utero exposure to maternal thyroid disease could programme the foetus to development of adiposity.

DESIGN

Cohort and case-cohort studies.

PARTICIPANTS

Pregnant women from the Danish National Birth Cohort and their 7-year-old children.

MEASUREMENTS

Maternal thyroid disease (hyperthyroidism and hypothyroidism) was assessed from registrations of diagnoses and treatment (n = 71 706) or from the measurement of thyroid-stimulating hormone (TSH) in a stored blood sample from the early pregnancy (n = 7624). Maternal prepregnancy body mass index (BMI) and child BMI at 7 years of age were used to define overweight and obesity, and associations were evaluated using regression models adjusting for potential confounders.

RESULTS

No association was found between maternal thyroid disease in pregnancy and child overweight (hyperthyroidism: adjusted risk ratio (aRR): 1.02 (95% confidence interval (CI): 0.58-1.82); hypothyroidism: 1.31 (0.86-1.97)) or obesity (hyperthyroidism: 0.96 (0.53-1.75); hypothyroidism: 1.25 (0.76-2.05)). On the other hand, pregnant women with hypothyroidism in early pregnancy had a higher risk of being overweight (aRR: 1.20 (95% CI: 1.03; 1.41)) and obese (1.45 (1.07; 1.96)), whereas women with hyperthyroidism had a lower risk of being overweight (0.79 (0.64; 0.98)).

CONCLUSIONS

Results provide no evidence that maternal thyroid disease in pregnancy programmes adiposity in the child, but corroborate an association between maternal thyroid disease and adiposity in the mother.

Isolated maternal hypothyroxinemia and adverse pregnancy outcomes: A systematic review

Maternal thyroid hormones are vital for a normal pregnancy and the development of fetus and childhood; inadequate availability of thyroid hormones during pregnancy is associated with adverse pregnancy outcomes. Isolated maternal hypothyroxinemia (IMH) is defined as a low maternal T4 in the absence of TSH elevation. This systematic review aimed to investigate the association between IMH and adverse pregnancy outcomes. PubMed, Scopus and Web of science were searched for retrieving observational studies published up to September 2020, investigating the association of IMH with adverse pregnancy outcomes. From a total of 308 articles, 17 met our eligibility criteria and were used for the purpose of the present study. Definition of IMH varied in different studies. While some studies reported no adverse pregnancy outcomes for IMH, other studies found a positive association between first trimester IMH and feto-maternal outcomes including gestational hypertension, gestational diabetes, preterm delivery, fetal distress, small for gestational age, musculoskeletal malformations, spontaneous abortion, placental abruption and macrosomia. IMH, identified in the second trimester was associated with an increase in the risk of gestational diabetes, and hypertensive disorders of pregnancy in one study. There is no consensus on the adverse effects of IMH on pregnancy outcomes. Further comprehensive cohort studies using one standard definition for IMH, with large sample size and control of important confounders such as iodine status and maternal Thyroid peroxidase antibody (TPOAb) are needed for precise assessment of this association.

Association of Cord Blood Thyroid-Stimulating Hormone Levels with Maternal, Delivery and Infant Factors

Abstract Introduction: This study examined maternal, delivery and infant factors associated with cord thyroid-stimulating hormone (TSH) concentrations in an Asian population. Methods: The Growing Up in Singapore Towards healthy Outcomes (GUSTO) study is a mother–offspring birth cohort from 2 major hospitals in Singapore. Cord serum TSH was measured using the Abbott ARCHITECT TSH Chemiluminescent Microparticle Immunoassay and the ADVIA Centaur TSH-3 Immunoassay. After excluding infants with a maternal history of thyroid disease, screening cord TSH results from 604 infants were available for multivariable regression analysis in relation to the factors of interest. Results: Babies born by vaginal delivery had significantly higher cord serum TSH concentrations than babies born by caesarean section. Cord serum TSH concentrations differed significantly by measurement method. There was no association of cord TSH concentrations with ethnicity, sex, birth weight, gestational age, maternal body mass index, gestational weight gain, gestational diabetes mellitus status and other maternal, delivery and infant factors studied. Conclusion: Interpretation of cord serum TSH results may need to take into account mode of delivery and measurement method. Keywords: Cord blood, Growing Up in Singapore Towards healthy Outcomes, GUSTO, perinatal

Family history is a predictor of current preterm birth

BACKGROUND

Reliable prediction of spontaneous preterm birth remains limited, particularly for nulliparous and multiparous women without a personal history of preterm birth. Although previous preterm birth is a risk factor for recurrent preterm birth, most spontaneous preterm births occur in women with no previous history of preterm birth.

OBJECTIVE

This study aimed to determine whether patients' self-reported maternal family history of preterm births among siblings and across 3 generations was an independent risk factor for spontaneous preterm births after controlling for potential confounders.

STUDY DESIGN

This was a retrospective analysis of a prospectively acquired cohort using a comprehensive single, academic center database of deliveries from August 2011 to July 2017. The objective of the current analysis was to evaluate the risk of preterm birth among women with and without a family history of preterm birth. All subjects in the database were directly queried regarding familial history across 3 generations, inclusive of obstetrical morbidities. Index subjects with probable indicated preterm birth (eg, concurrent diagnosis of preeclampsia; hemolysis, elevated liver enzymes, and low platelet count; or placenta previa or placenta accreta) were excluded, as were nonsingleton pregnancies. Univariate and multivariate analyses with logistic regression were used to determine significance and adjusted relative risk.

RESULTS

In this study, 23,816 deliveries were included, with 2345 (9.9%) born prematurely (<37 weeks' gestation). Across all subjects, preterm birth was significantly associated with a maternal family history of preterm birth by any definition (adjusted relative risk, 1.44; P<.001), and the fraction of preterm birth occurring in women with a positive family history increased with decreasing gestational age at which the index subjects of preterm birth occurred. For nulliparous women, a history in the subject's sister posed the greatest risk (adjusted relative risk, 2.25; P=.003), whereas for multiparous women with no previous preterm birth, overall family history was most informative (P=.003). Interestingly, a personal history of the index subject herself being born preterm presented the greatest individual risk factor (adjusted relative risk, 1.94; P=.004).

CONCLUSION

Spontaneous preterm birth in the current pregnancy was significantly associated with a maternal family history of preterm birth among female relatives within 3 generations and notably sisters. The risk persisted among gravidae without a previous preterm birth, demonstrating the capacity for familial history to independently predict risk of spontaneous preterm birth even in the context of a negative personal history. This study provides evidence that self-reported maternal family history is relevant in a US population cohort and across more distant generations than has previously been reported.

The association of serologically documented maternal thyroid conditions during pregnancy with bipolar disorder in offspring

OBJECTIVES

Higher rates of thyroid conditions are reported in individuals with bipolar disorder. However, no study to date has considered whether maternal thyroid conditions during pregnancy are associated with offspring risk of bipolar disorder, even though the fetus exclusively relies on maternal thyroid hormones through the early second trimester. We therefore examined the association between offspring bipolar disorder and serologically documented maternal thyroid conditions.

METHODS

The study was based on a nested case-control design that utilized data from the Child Health and Development Study, a birth cohort that enrolled pregnant women from 1959 to 1966. Eighty-five cases with DSM-IV-TR were ascertained and matched to controls (1:2) by date of birth, sex, gestational timing of the serum draws, and residence in Alameda County the first year receiving treatment. Archived prenatal maternal serum drawn during early to mid-gestation was used to measure two thyroid hormones, free thyroxine (fT4) and thyroid stimulating hormone (TSH). Subclinical and clinical hypothyroxinemia, hypothyroidism, and hyperthyroidism were determined based on standard methods.

RESULTS

Exposure to maternal hypothyroxinemia was associated with a five-fold increased risk of offspring bipolar disorder with psychotic features, but not without psychotic features. In stratified analysis, female offspring demonstrated increased risk for bipolar disorder with exposure to maternal hypothyroxinemia. No significant association was found between maternal hypothyroidism and offspring bipolar disorder.

CONCLUSIONS

These findings suggest that prenatal thyroid hormone deficiency, particularly a thyroid condition marked by low levels of thyroxine, may be an important developmental mechanism related to the risk of bipolar disorder with psychotic features.

Cluster Analysis: A New Approach for Identification of Underlying Risk Factors and Demographic Features of First Trimester Pregnancy Women

Thyroid pathology is reported internationally in 5-10% of all pregnancies. The overall aim of this research was to determine the prevalence of hypothyroidism and risk factors during the first trimester screening in a Mexican patients sample. We included the records of 306 patients who attended a prenatal control consultation between January 2016 and December 2017 at the Women's Institute in Monterrey, Mexico. The studied sample had homogeneous demographic characteristics in terms of age, weight, height, BMI (body mass index) and number of pregnancies. The presence of at least one of the risk factors for thyroid disease was observed in 39.2% of the sample. Two and three clusters were identified, in which patients varied considerably among risk factors, symptoms and pregnancy complications. Compared to Cluster 0, one or more symptoms or signs of hypothyroidism occurred, while Cluster 1 was characterized by healthier patients. When three clusters were used, Cluster 2 had a higher TSH (thyroid stimulating hormone) value and pregnancy complications. There were no significant differences in perinatal variables. In addition, high TSH levels in first trimester pregnancy are characterized by pregnancy complications and decreased newborn weight. Our findings underline the high degree of disease heterogeneity with existing pregnant hypothyroid patients and the need to improve the phenotyping of the syndrome in the Mexican population.

Thyroid hormones profile among obese pregnant Sudanese women

BACKGROUND

Previous studies evaluating thyroid function among obese pregnant women failed to demonstrate a consistent pattern of thyroid hormones profile, probably due to the variations in biological/environmental determinants of thyroid function in different countries.

AIM

The aim of the study was to evaluate thyroid hormones profile in Sudanese pregnant women with varying degrees of obesity.

PATIENTS AND METHODS

Obstetric/sociodemographic characteristics were gathered from 178 singleton pregnant Sudanese women using questionnaires. Weight and height were measured; body mass index (BMI) was calculated and categorized into four groups: Underweight (BMI <18.5 kg/m²), normal weight (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²), and obese (≥30 kg/m²). Free triiodothyronine (FT3), free thyroxin (FT4), and thyroid-stimulating hormone (TSH) were measured.

RESULTS

Of the 178 enrolled women, 9 (5.1%), 52 (29.2%), 73 (41.0%), and 44 (24.7%) were underweight, normal BMI, overweight, and obese, respectively. FT3 level was significantly higher in obese women compared with normal BMI (P=0.004) as well as overweight women (P=0.015). Higher FT3 levels were significantly associated with obesity (odds ratio [OR]=9.5, 95% confidence interval [CI] =3.1-29.0, P<0.001). Lower levels of FT4 were significantly associated with overweight (OR=0.06, 95% CI=0.007-0.58, P=0.015) and obesity (OR=0.048, 95% CI=0.004-0.5, P=0.018). Based on linear regression analysis, BMI was positively associated with FT3 (4.7 pmol/l, P<0.001) and negatively associated with FT4 (-8.26 pmol/l, P=0.001).

CONCLUSIONS

BMI correlates with FT3 differently compared to FT4. Pregnant women with higher BMI are likely to have higher levels of FT3, but lower FT4. In contrast, TSH levels were comparable in different BMI groups.

RELEVANCE FOR PATIENTS

Increased iodothyronine 5´deiodinase (5´D) activity associated with obesity may give an explanation for thyroid profile in those with higher BMI. High 5´ activity increases FT3 at the expense of FT4. Alternatively, high FT3 and low FT4 are expected to feedback differently on TSH, which explains the loss of positive correlation between BMI and TSH.

Interaction effect of obesity and thyroid autoimmunity on the prevalence of hyperthyrotropinaemia

PURPOSE

The role of thyroid autoimmunity in the association between obesity and hyperthyrotropinaemia remains unclear. We aimed to assess the relationship between obesity, autoimmunity, and hyperthyrotropinaemia.

METHODS

In this population-based cross-sectional study, 12531 Chinese individuals (18-80 years) with thyroid function test were categorized into three groups by body mass index (BMI) and were categorized into three layers by thyroid autoantibodies. Multivariate logistic regression was employed to assess the correlation and interaction effect.

RESULTS

There was no significant difference in prevalence of hyperthyrotropinaemia (P = 0.637) among three BMI groups. After stratification, the difference of serum thyrotropin (P < 0.01) and prevalence of hyperthyrotropinaemia (P < 0.01) between the three groups have significant linear trends at the positive levels of thyroid peroxidase antibody (TPOAb) or/and thyroglobulin antibody (TgAb). When TPOAb and TgAb were positive, the risk of hyperthyrotropinaemia increased 1.857-fold in overweight group and 2.201-fold in obese group compared with normal group. Compared with negative TPOAb and TgAb, the risk of hyperthyrotropinaemia for individuals with two positive antibodies increased 3.310-fold, 4.969-fold, and 5.122-fold in the three BMI groups. The adjusted OR (95% CI) for interaction were 1.033 (0.752-1.419) for overweight and one positive antibodies, 1.935 (1.252-2.990) for overweight and two positive antibodies, 1.435 (0.978-2.105) for obesity and one positive antibodies and 2.191 (1.252-3.832) for obesity and two positive antibodies.

CONCLUSION

Overweight and obesity were associated with hyperthyrotropinaemia only in presence of thyroid autoimmunity, and obesity might aggravate the pathogenic effect of autoimmunity on hyperthyrotropinaemia. There was an interaction effect between obesity and autoimmunity on the prevalence of hyperthyrotropinaemia.

Early-life programming of adipose tissue

Worldwide obesity is increasing at an alarming rate in children and adolescents, with the consequent emergence of co-morbidities. Moreover, the maternal environment during pregnancy plays an important role in obesity, contributing to transgenerational transmission of the same and metabolic dysfunction. White adipose tissue represents a prime target of metabolic programming induced by maternal milieu. In this article, we review adipose tissue physiology and development, as well as maternal influences during the perinatal period that may lead to obesity in early postnatal life and adulthood. First, we describe the adipose tissue cell composition, distribution and hormonal action, together with the evidence of hormonal factors participating in fetal/postnatal programming. Subsequently, we describe the critical periods of adipose tissue development and the relationship of gestational and early postnatal life with healthy fetal adipose tissue expansion. Furthermore, we discuss the evidence showing that adipose tissue is an important target for nutritional, hormonal and epigenetic signals to modulate fetal growth. Finally, we describe nutritional, hormonal, epigenetic and microbiome changes observed in maternal obesity, and whether their disruption alters fetal growth and adiposity. The presented evidence supports the developmental origins of health and disease concept, which proposes that the homeostatic system is affected during gestational and postnatal development, impeding the ability to regulate body weight after birth, thereby resulting in adult obesity. Consequently, we anticipate that promoting a healthy early-life programming of adipose tissue and increasing the knowledge of the mechanisms by which maternal factors affect the health of future generations may offer novel strategies for explaining and addressing worldwide health problems such as obesity.

Association Between Maternal Thyroid Hormones and Birth Weight at Early and Late Pregnancy

CONTEXT

Previous studies suggest that maternal thyroid function affects fetal growth, but the association between combined thyroid hormones from early to late pregnancy and newborn birth weight remains unknown.

OBJECTIVE

To explore the association of maternal thyroid function during early and late pregnancy with birth weight.

DESIGN

A large prospective cohort study of a Chinese population.

SETTING

This study recruited pregnant women who underwent first-trimester prenatal screenings at the International Peace Maternity and Child Health Hospital between January 2013 and December 2016.

PARTICIPANTS

This study enrolled 46,186 mothers in whom TSH, free thyroxine (FT4), T3, and thyroid peroxidase antibody concentrations were measured in the first and third trimesters and in whom data on birth weight were available.

MAIN OUTCOME MEASURES

Birth weight, small for gestational age, large for gestational age (LGA).

RESULTS

A higher TSH or FT4 concentration, or a lower T3 concentration, during the first or third trimester was associated with a lower birth weight. The lowest percentiles of maternal FT4 (FT4 < 2.5th percentile) in both trimesters were associated with a 0.34-SD higher birth weight. The effect estimates were greater in those in the first trimester (0.23 SD) or in the third trimester (0.17 SD). The association of maternal TSH and FT4 with birth weight differed according to fetal sex.

CONCLUSIONS

Persistently low FT4 concentrations throughout pregnancy were associated with higher birth weight and an increased risk of LGA. Based on these findings, we recommend monitoring mildly altered concentrations of thyroid hormone throughout pregnancy.

Maternal Heavy Metal Exposure, Thyroid Hormones, and Birth Outcomes: A Prospective Cohort Study

CONTEXT

Maternal thyroid hormones during pregnancy play a critical role in fetal development. However, whether maternal heavy metal exposure affects their thyroid hormones and the effects on fetal growth are still unclear.

OBJECTIVE

To explore the effect of heavy metal exposure on maternal thyroid hormones and the potential mediation role of thyroid hormones on birth outcomes.

METHODS

Concentrations of heavy metals in urine samples and thyroid hormones in blood samples of 675 pregnant women were measured during early pregnancy in a cohort study conducted in China. Multivariable linear regressions were applied to explore the associations of maternal urinary heavy metal levels with both maternal thyroid hormones and birth outcomes. Mediation analyses were performed to assess the mediation role of thyroid hormones in these associations.

RESULTS

Maternal urinary vanadium (V) exhibited an inverse association with free T3 (FT3) and FT3/free T4 (FT4) ratio levels. Urinary arsenic (As) and lead (Pb) had inverse relationships with FT3. We also observed the positive associations of maternal FT3 and FT3/FT4 ratio with birthweight. The mediation analyses suggested that 5.33% to 30.57% of the associations among V, As, and Pb levels and birth size might be mediated by maternal FT3 or FT3/FT4 ratio.

CONCLUSIONS

We have shown that maternal exposures to V, As, and Pb at early pregnancy were associated with decreased maternal FT3 or FT3/FT4 ratio, which might contribute to reduced birthweight. Mediation analyses indicated that maternal thyroid hormone was a possible mediator of the association between urinary heavy metals and birth size.

Effects of nutrition restriction of fat- and lean-line broiler breeder hens during the laying period on offspring performance, blood biochemical parameters, and hormone levels

To evaluate the effects of maternal undernutrition on the performance, blood biochemical indexes, and hormone levels of broiler chicks, two broiler breeder lines (a fat line and lean line) were given either 100% or 75% of the daily feed intake recommended by the Chinese Ministry of Agriculture from 27 to 54 wk. All hens were fed the same basal corn-soybean diet. Fertile eggs were collected and hatched. All chicks were fed the same basal diet for 56 d. Then, chick performance, blood biochemical indexes, and hormone levels were measured. The results showed that there were interactions between maternal nutrition and line for some parameters, such as the kidney index, glucose, triglyceride, insulin, glucagon, leptin, and triiodothyronine (P < 0.05). Chicks of the fat line had a lower level of serum glucose, triglyceride, albumin, glutamic-pyruvic transaminase, insulin, and thyroxin than those of the lean line (P < 0.05), but the opposite trend was seen for birth weight, heart index, leptin, and triiodothyronine (P < 0.05). Maternal undernutrition decreased the birth weight and thymus index (day 28) of offspring (P < 0.05), but these effects disappeared by day 56. Maternal undernutrition decreased glucose (day 28), urea nitrogen (day 56), creatinine (day 56), glutamic-pyruvic transaminase (day 56), creatinine kinase (day 56), and leptin (day 56) levels in the offspring's serum (P < 0.05) but increased creatinine (day 28), total protein (day 28), glutamic-pyruvic transaminase (day 28), and glucagon (day 28) levels (P < 0.05). In conclusion, different lines have different metabolic processes. Maternal nutrition restriction during the laying period did have effects on the offspring, and the compensation by offspring reduced the effect of maternal nutrition restriction.

Maternal BMI, Peripheral Deiodinase Activity, and Plasma Glucose: Relationships Between White Women in the HAPO Study

OBJECTIVES

Explore the maternal body mass index (BMI) relationship with peripheral deiodinase activity further. Examine associations between deiodinase activity, glucose, and C-peptide. Consider findings in the historical context of related existing literature.

DESIGN

Identify fasting plasma samples and selected demographic, biophysical, and biochemical data from a subset of 600 randomly selected non-Hispanic white women recruited in the Hyperglycemia Adverse Pregnancy Outcomes (HAPO) study, all with glucose tolerance testing [545 samples sufficient to measure TSH, free T4 (fT4), and T3]. Exclude highest and lowest 1% TSH values (535 available for analysis). Assess deiodinase activity by using T3/fT4 ratios. Among women with and without gestational diabetes mellitus (GDM), compare thyroid measurements, C-peptide, and other selected data. Examine relationships independent of GDM status between BMI and thyroid hormones and between thyroid hormones and glucose and C-peptide.

RESULTS

Levels of BMI, T3/fT4 ratio, and T3 were significantly higher among women with GDM (P = 0.01, 0.005, and 0.001, respectively). Irrespective of GDM status, maternal BMI was associated directly with both T3/fT4 ratio (r = 0.40, P < 0.001) and T3 (r = 0.34, P < 0.001) but inversely with fT4 (r = -0.21, P < 0.001). In turn, fasting thyroid hormone levels (most notably T3/fT4 ratio) were directly associated with maternal glucose [z score sum (fasting, 1, 2 hours); r = 0.24, P < 0.001] and with C-peptide [z score sum (fasting, 1 hour); r = 0.27, P < 0.001].

CONCLUSIONS

Higher BMI was associated with increased deiodinase activity, consistent with reports from elsewhere. Increased deiodinase activity, in turn, was associated with higher glucose. Deiodinase activity accounts for a small percentage of z score sum glucose.

Maternal smoking and high BMI disrupt thyroid gland development

BACKGROUND

Maternal lifestyle factors, including smoking and increased body weight, increase risks of adult diseases such as metabolic syndrome and infertility. The fetal thyroid gland is essential for the control of fetal metabolic rate, cardiac output, and brain development. Altered fetal thyroid function may contribute to increased disease onset later in life. Here, we investigated the impact of maternal smoking and high maternal weight on human fetal thyroid function during the second trimester.

METHODS

Thyroid glands and plasma were collected from fetuses electively terminated in the second trimester (normally progressing pregnancies). Plasma total triiodothyronine (T3) and total thyroxine (T4) were measured by solid-phase extraction-liquid chromatography-tandem mass spectrometry. Fetal plasma thyroid-stimulating hormone (TSH) levels were measured using a multiplex assay for human pituitary hormones. Histology and immunolocalization of thyroid developmental markers were examined in thyroid sections. Transcript levels of developmental, functional, apoptotic, and detoxification markers were measured by real-time PCR. Statistical analyses were performed using multivariate linear regression models with fetal age, sex, and maternal smoking or maternal body mass index (BMI) as covariates.

RESULTS

Maternal smoking was associated with significant changes in fetal plasma T4 and TSH levels during the second trimester. Smoke-exposed thyroids had reduced thyroid GATA6 and NKX2-1 transcript levels and altered developmental trajectories for ESR2 and AHR transcript levels. Maternal BMI > 25 was associated with increased fetal thyroid weight, increased plasma TSH levels, and abnormal thyroid histology in female fetuses. Normal developmental changes in AHR and ESR1 transcript expression were also abolished in fetal thyroids from mothers with BMI > 25.

CONCLUSIONS

For the first time, we show that maternal smoking and high maternal BMI are associated with disturbed fetal thyroid gland development and endocrine function in a sex-specific manner during the second trimester. These findings suggest that predisposition to post-natal disease is mediated, in part, by altered fetal thyroid gland development.

Effect of maternal and neonatal factors on neonatal thyroid stimulating hormone: Results from a population-based prospective cohort study in China

OBJECTIVE

Neonatal TSH screening is effective in detecting congenital hypothyroidism and estimating iodine status in a given population, but various factors influence TSH levels. The aim of this study was to evaluate the effect of maternal and neonatal factors on neonatal TSH levels.

DESIGN AND SETTING

Data were obtained from an ongoing prospective cohort study. A total of 988 pregnant women and their newborn infants participated in the study from April 2015 to May 2017 at Tianjin Maternal and Child Health Center and Tanggu Maternity Hospital in Tianjin, China. Maternal demographic information, including age, height, and parity, was recorded by questionnaire. Fasting blood and urinary samples were collected from all pregnant women. After parturition, information on gestation duration, mode of delivery, neonatal sex, neonatal TSH, neonatal birth weight, and neonatal birth height were recorded.

RESULTS

Maternal age, maternal BMI, gestation duration, parity, and neonatal birth weight and height were significantly correlated with neonatal TSH (p < 0.05). Quantile regression revealed that maternal age, TSH, FT₄, and gestation duration were positively correlated with neonatal TSH level. A logistic regression model identified maternal BMI, TSH, and birth height as risk factors for having neonatal TSH > 5 mIU/L (p < 0.05).

CONCLUSION

Neonatal TSH levels are dynamic and may be affected by several maternal and neonatal factors including maternal age, TSH, FT₄, and birth weight and height. Identification of these confounders is useful for assessing the status of neonatal thyroid development. STRENGTHS AND LIMITATIONS OF THIS STUDY: (1) Iodine deficiency disorder has generally been eliminated, so the median urinary iodine concentration of pregnancy is higher than 150 μg/L even in mildly or moderately iodine deficient areas. (2) Unlike many other studies, which did not consider the complexity of factors or examined only one or two variables, this study used a multivariate model to analyze the data. (3) This study examined numerous high-risk factors in pregnant women and considered the biological interrelation between them. Future studies should consider these confounding factors for neonatal TSH levels and establish a proper neonatal TSH range for monitoring the iodine status of a population or diagnosing congenital hypothyroidism.

Macrosomia. A Systematic Review of Recent Literature

Background and aims: The obesity and overweight rate among women of childbearing age and fetal macrosomia associated with different birth injuries are very frequent all over the world and with an increasing incidence. The huge amount of published literature on this topic in the last decade is putting the practioners in a very challenging position. Material and method: We have done a systematic review on the recent literature (last five years) based on science direct database. Results: A total of 5990 articles were identified and after successive exclusion of some of them, 48 were deeply analyzed. The results were grouped in following topics: risk factors for fetal macrosomia, the pathophysiology of macrosomia, prenatal clinical and lab diagnosis and prevention of macrosomia. Conclusions: Considering the maternal, fetal and neonatal complications of macrosomia, the counseling, and monitoring of the pregnant women risk group are of particular importance for adopting a low calorie / low glycemic diet and avoiding a sedentary behaviour. Long-term follow-up of the mother and the macrosomic baby is required because of the risk of obesity, diabetes, hypertension, and metabolic syndrome later in life.

Adiposity and weight gain during pregnancy associate independently with behavior of infant rhesus monkeys (Macaca mulatta)

Growing evidence identifies maternal adiposity as a potentially modifiable risk factor for adverse neurodevelopment. This retrospective cohort analysis examined whether maternal prepregnancy adiposity and gestational weight gain were associated with behavioral outcomes in 173 rhesus macaque infants at the California National Primate Research Center. Dams conceived indoors, had uncomplicated pregnancies, delivered vaginally, and reared infants indoors. Infants underwent standardized biobehavioral analysis at 90-120 days of age from 3/2001-5/2015. Offspring of mothers with greater baseline adiposity or gestational weight gain exhibited a pattern of poor adaptability characterized by greater emotionality as the assessments proceeded, blunted affective response to a human intruder challenge, and reduced interest in novel stimuli which is associated with poorer social functioning later in life. They also had lower cortisol levels following dexamethasone suppression, perhaps a response to cortisol excess during gestation. These results amplify growing public health concerns implicating maternal adiposity in impaired fetal neurobehavioral programming.

Peripheral deiodinase activity: A potential explanation for the association between maternal weight and gestational hyperglycemia

Background

High maternal weight is known to associate with both low free thyroxine and gestational diabetes mellitus. We explore a deiodinase-related mechanism that may help explain these associations.

Methods

Among 108 women receiving routine oral glucose tolerance testing for gestational diabetes mellitus, we collected biophysical data and measured free thyroxine and total triiodothyronine, using residual plasma samples.

Results

Fasting triiodothyronine/free thyroxine ratio and triiodothyronine were higher among women with gestational diabetes mellitus (p = 0.02; p = 0.04). The triiodothyronine/free thyroxine ratio and triiodothyronine measurements at 2 h were associated with weight (r = 0.20, p = 0.04; r = 0.22, p = 0.02); free thyroxine showed a non-significant inverse weight relationship (r = -0.06, p = 0.55). Glucose at all four intervals was associated with triiodothyronine/free thyroxine ratios, and triiodothyronine at 2 h. In stepwise regression, triiodothyronine/free thyroxine ratio predicted glucose more strongly than did weight.

Conclusion

These relationships may be explained by higher maternal weight inducing peripheral deiodinase activity, resulting in higher plasma glucose (via triiodothyronine stimulation) and thereby increasing gestational diabetes mellitus risk.

Advances in TRH signaling

The activity of the hypothalamus-pituitary-thyroid axis (HPT) is coordinated by hypophysiotropic thyrotropin releasing hormone (TRH) neurons present in the paraventricular nucleus of the hypothalamus. Hypophysiotropic TRH neurons act as energy sensors. TRH controls the synthesis and release of thyrotropin, which activates the synthesis and secretion of thyroid hormones; in target tissues, transporters and deiodinases control their local availability. Thyroid hormones regulate many functions, including energy homeostasis. This review discusses recent evidence that covers several aspects of TRH role in HPT axis regulation. Knowledge about the mechanisms of TRH signaling has steadily increased. New transcription factors engaged in TRH gene expression have been identified, and advances made on how they interact with signaling pathways and define the dynamics of TRH neurons response to acute and/or long-term influences. Albeit yet incomplete, the relationship of TRH neurons activity with positive energy balance has emerged. The importance of tanycytes as a central relay for the feedback control of the axis, as well as for HPT responses to alterations in energy balance, and other stimuli has been reinforced. Finally, some studies have started to shed light on the interference of prenatal and postnatal stress and nutrition on HPT axis programing, which have confirmed the axis susceptibility to early insults.

Generation and validation of a universal perinatal database and biospecimen repository: PeriBank

OBJECTIVE

There is a dearth of biospecimen repositories available to perinatal researchers. In order to address this need, here we describe the methodology used to establish such a resource.

STUDY DESIGN

With the collaboration of MedSci.net, we generated an online perinatal database with 847 fields of clinical information. Simultaneously, we established a biospecimen repository of the same clinical participants.

RESULTS

The demographic and clinical outcomes data are described for the first 10 000 participants enrolled. The demographic characteristics are consistent with the demographics of the delivery hospitals. Quality analysis of the biospecimens reveals variation in very few analytes. Furthermore, since the creation of PeriBank, we have demonstrated validity of the database and tissue integrity of the biospecimen repository.

CONCLUSION

Here we establish that the creation of a universal perinatal database and biospecimen collection is not only possible, but allows for the performance of state-of-the-science translational perinatal research and is a potentially valuable resource to academic perinatal researchers.