Fetal growth versus birthweight: the role of placenta versus other determinants

Maternal body mass index, birthweight, and placental glucose metabolism: evidence for a role of placental hexokinase

BACKGROUND

The principal fetal energy source is glucose provided by the placental transfer of maternal glucose. However, the placenta's glucose consumption exhibits considerable variation. Hexokinase is the first and one of the rate-limiting enzymes of glycolysis that phosphorylates glucose to glucose-6-phosphate. The role of placental hexokinase activity in human placental glucose metabolism is unknown.

OBJECTIVE

This study aimed to test the hypothesis that placental hexokinase activity is related to maternal body mass index, placental glucose uptake and consumption, and birthweight.

STUDY DESIGN

Overall, 67 healthy pregnant participants at term were included in this study at Oslo University Hospital, Oslo, Norway. Placental hexokinase activity was measured by using a colorimetric assay. The mass of glucose taken up by the uteroplacental unit and the fetus was obtained by measuring arteriovenous glucose differences combined with Doppler assessment of uterine and umbilical blood flow. Blood samples were obtained from the maternal radial artery, uterine vein, and umbilical artery and vein. The uteroplacental glucose consumption constituted the difference between uteroplacental and fetal glucose uptakes. The Spearman rank correlation was performed for statistical analyses to study the correlation of placental hexokinase activity (milliunit per milligram of protein) with prepregnancy body mass index, maternal glucose and insulin, birthweight, uteroplacental glucose uptake and consumption, and fetal glucose uptake (micromole per minute). Partial rank correlation analysis was performed when controlling for hours of fasting or placental weight.

RESULTS

Hexokinase activity was detectable in all placental tissue samples. The mean activity was 19.6 (standard deviation, 4.64) mU/mg protein. Placental hexokinase activity correlated positively with prepregnancy body mass index (Spearman rho=0.33; P=.006). On controlling for hours of fasting, hexokinase activity showed positive correlations with both maternal glucose (r=0.30; P=.01) and insulin (r=0.28; P=.02). Hexokinase activity was positively correlated with uteroplacental glucose uptake (Spearman rho=0.31; P=.01) and consumption (Spearman rho=0.28; P=.02). Hexokinase activity did not correlate with fetal glucose uptake. On controlling for placental weight, hexokinase activity showed a positive correlation with birthweight (r=0.31; P=.01).

CONCLUSION

Our findings suggest that placental hexokinase, being crucial for uteroplacental retention of glucose for disposition, is related to both maternal body mass index and birthweight independent of placental weight. Placental hexokinase may play a central role in the relationship between maternal glucose dysregulation and fetal growth. Thus, the current study supports the need to develop clinically useful tools to assess the metabolic properties of the placenta.

Impact of birth weight to placental weight ratio and other perinatal risk factors on left ventricular dimensions in newborns: a prospective cohort analysis

OBJECTIVES

To investigate the association between birth weight to placental weight (BW/PW) ratio, and echocardiographic left ventricle (LV) morphology at birth, while accounting for other relevant perinatal factors.

METHODS

A prospective cohort study was conducted on neonates at NewYork-Presbyterian Brooklyn Methodist Hospital from 2014 to 2018, categorized by their BW/PW percentile. Missing data were imputed with principal component analysis. Chi-squared and one-way analysis of variance were used to compare BW/PW groups and the best regression model was selected using a genetic and backward stepwise algorithm.

RESULTS

We analyzed 827 neonates in three BW/PW groups: small (n=16), normal (n=488), and large (n=323). Placental thickness and smallest diameter were positively correlated with several LV parameters, including inter-ventricular septal thickness during diastole (IVSd) (p=0.002, p<0.001) and systole (IVSs) (p=0.001, p<0.001), LV posterior wall thickness at end of diastole (LVPWd) (p=0.003, p<0.001) and systole (LVPWs) (p<0.001, p<0.001), LV mass (p=0.017, p<0.001), and LV mass/volume (p=0.011, p<0.001). The BW/PW ratio correlated with an increased shortening fraction (estimate=0.29, 95 % CI 0.03-0.55, p=0.027). PW correlated with IVSs (p=0.019), while the longest placental diameter was linked to a decrease in LV internal dimension during diastole (LVIDd) (estimate=-0.07, p=0.039), LV mass (estimate=-0.11, p=0.024), and LV mass/volume (estimate=-0.55, p=0.005).

CONCLUSIONS

This study found that several placental factors, including the BW/PW ratio, can independently affect LV dimension and morphology, highlighting the importance of fetal growth and placental health in the physiological adaptation of the fetal heart. More research is needed to establish causation and inform newborn prevention strategies.

Maternal exposure to beta-Cypermethrin disrupts placental development by dysfunction of trophoblast cells from oxidative stress

As a broad-spectrum and efficient insecticide, beta-Cypermethrin (β-CYP) poses a health risk to pregnancy. It matters the mechanisms of maternal exposure to β-CYP for impacting reproductive health. The placenta, a transient organ pivotal for maternal-fetal communication during pregnancy, plays a crucial role in embryonic development. The effect of β-CYP exposure on the placenta and its underlying molecular mechanisms remain obscure. The objective of this study was to investigate the effect of β-CYP exposure on placental development and the function of trophoblast, as well as the underlying mechanisms through CD-1 mouse model (1, 10, 20 mg/kg.bw) and in vitro HTR-8/SVneo cell model (12.5, 25, 50, 100 μM). We found slower weight gain and reduced uterine wet weight in pregnant mice with maternal exposure to β-CYP during pregnancy, as well as adverse pregnancy outcomes such as uterine bleeding and embryo resorption. The abnormal placental development in response to β-CYP was noticed, including imbalanced placental structure and disrupted labyrinthine vascular development. Trophoblasts, pivotal in placental development and vascular remodeling, displayed abnormal differentiation under β-CYP exposure. This aberration was characterized by thickened trophoblast layers in the labyrinthine zone, accompanied by mitochondrial and endoplasmic reticulum swelling within trophoblasts. Further researches on human chorionic trophoblast cell lines revealed that β-CYP exposure induced apoptosis in HTR-8/SVneo cells. This induction resulted in a notable decrease in migration and invasion abilities, coupled with oxidative stress and the inhibition of the Notch signaling pathway. N-acetylcysteine (an antioxidant) partially restored the impaired Notch signaling pathway in HTR-8/SVneo cells, and mitigated cellular functional damage attributed to β-CYP exposure. Collectively, exposure to β-CYP induced oxidative stress and then led to inhibition of the Notch signaling pathway and dysfunction of trophoblast cells, ultimately resulted in abnormal placenta and pregnancy. These findings indicate Reactive Oxygen Species as potential intervention targets to mitigate β-CYP toxicity. The comprehensive elucidation contributes to our understanding of β-CYP biosafety and offers an experimental basis for preventing and managing its reproductive toxicity.

Maternal metabolic profiling across body mass index groups: An exploratory longitudinal study

INTRODUCTION

Increased BMI has been identified as a risk factor for most pregnancy complications, but the underlying metabolic factors mediating the detrimental effects of BMI are largely unknown. We aimed to compare metabolic profiles in overweight/obese women (body mass index [BMI] ≥ 25 kg/m2 ) and normal weight/underweight women (BMI < 25 kg/m2 ) across gestation. We also explored how gestational weight gain (GWG) affected maternal metabolic profiles.

MATERIAL AND METHODS

Exploratory nested case-control study based on a prospective longitudinal cohort of women who were healthy prior to pregnancy and gave birth at Oslo University Hospital from 2002 to 2008. The sample consisted of 48 women who were overweight/obese and 59 normal-weight/underweight women. Plasma samples from four time points in pregnancy (weeks 14-16, 22-24, 30-32 and 36-38) were analyzed by nuclear magnetic resonance spectroscopy and 91 metabolites were measured. Linear regression models were fitted for each of the metabolites at each time point.

RESULTS

Overweight or obese women had higher levels of lipids in very-low-density lipoprotein (VLDL), total triglycerides, triglycerides in VLDL, total fatty acids, monounsaturated fatty acids, saturated fatty acids, leucine, valine, and total branched-chain amino acids in pregnancy weeks 14-16 compared to underweight and normal-weight women. Docosahexaenoic acid and degree of unsaturation were significantly lower in overweight/obese women in pregnancy weeks 36-38. In addition, overweight or obese women had higher particle concentration of XXL-VLDL and glycoprotein acetyls (GlycA) at weeks 14-16 and 30-32. GWG did not seem to affect the metabolic profile, regardless of BMI group when BMI was treated as a dichotomous variable, ≥25 kg/m2 (yes/no).

CONCLUSIONS

Overweight or obese women had smaller pregnancy-related metabolic alterations than normal-weight/underweight women. There was a trend toward higher triglyceride and VLDL particle concentration in overweight/obese women. As this was a hypothesis-generating study, the similarities with late-onset pre-eclampsia warrant further investigation. The unfavorable development of fatty acid composition in overweight/obese women, with possible implication for the offspring, should also be studied further in the future.

Macroscopic examination of gynaecological specimens: a critial and often underemphasised aspect of pathological reporting

Pathological examination of surgical specimens and compilation of a surgical pathology report comprises a series of events which includes macroscopic examination and tissue sampling, either complete or selected. This step is critical but often overlooked in the literature and not given the attention it deserves. In this review, we discuss the macroscopic examination and grossing of gynaecological pathology specimens, with reference to national and international protocols. We provide guidance as to the degree of sampling necessary in different scenarios and stress that a common-sense approach is necessary with flexibility in the degree of sampling depending on a variety of factors.

Increased ferroptosis in leukocytes from preeclamptic women involving the long non-coding taurine upregulated gene 1 (TUG1)

BACKGROUND

Ferroptosis plays a key role in placental development and physiology, and abnormal ferroptosis has been implicated in trophoblast injury leading to preeclampsia (PE). We hypothesize that leukocytes isolated from PE exhibit increased ferroptosis and that extracellular vesicles contain long non-coding (lnc) RNA/mRNAs that modulate oxidative stress and iron toxicity in vascular endothelial cells.

METHODS

We measured the expression of key regulators of ferroptosis in leukocytes and extracellular vesicles as well as circulating biomarkers of iron homeostasis and oxidative stress in plasma from women with/without PE at different timepoints during pregnancy. For markers that were dysregulated, we assessed their temporal correlation with established markers of disease activity and marker of endothelial activation. For markers dysregulated in early pregnancy, we assessed their ability to predict the development of PE.

RESULTS

We found decreased lncRNA/mRNAs in leukocytes, but not extracellular vesicles, in PE that may modulate oxidative stress and iron toxicity. This decrease in anti-ferroptotic markers does not appear to be related to maternal disease activity or plasma oxidative stress status but rather to attenuated anti-inflammatory expression in these cells. Circulating ferritin was elevated in PE, supporting the hypothesis that PE represents a disbalance in iron homeostasis. Low lncRNA taurine upregulated gene 1 RNA levels in leukocytes at 22-24 weeks were strongly associated with the development of PE.

CONCLUSIONS

Our findings suggest that maternal leukocytes in PE show decreased anti-ferroptotic activity that correlates with anti-inflammatory expression. Moreover, some of these changes in ferroptotic activity appear to precede the development of PE.

Associations of offspring birthweight and placental weight with subsequent parental coronary heart disease: survival regression using the walker cohort

Low birth weight (BW) is consistently correlated with increased parental risk of subsequent cardiovascular disease, but the links with offspring placental weight (PW) are mostly unexplored. We have investigated the associations between parental coronary heart disease (CHD) and offspring BW and PW using the Walker cohort, a collection of 48,000 birth records from Dundee, Scotland, from the 1950s and 1960s. We linked the medical history of 13,866 mothers and 8,092 fathers to their offspring's records and performed Cox survival analyses modelling maternal and paternal CHD risk by their offspring's BW, PW, and the ratio between both measurements. We identified negative associations between offspring BW and both maternal (hazard ratio [HR]: 0.91, 95% confidence interval [CI]: 0.88-0.95) and paternal (HR: 0.96, 95% CI: 0.93-1.00) CHD risk, the stronger maternal correlation being consistent with previous reports. Offspring PW to BW ratio was positively associated with maternal CHD risk (HR: 1.14, 95% CI: 1.08-1.21), but the associations with paternal CHD were not significant. These analyses provide additional evidence for intergenerational associations between early growth and parental disease, identifying directionally opposed correlations of maternal CHD with offspring BW and PW, and highlight the importance of the placenta as a determinant of early development and adult disease.

Platelet and mitochondrial RNA is decreased in plasma-derived extracellular vesicles in women with preeclampsia-an exploratory study

BACKGROUND

Circulating extracellular vesicles (EVs) are increased in preeclampsia (PE) and are associated with severity and progression. We examined in this exploratory cohort study if the mRNAs and long noncoding RNAs (lncRNAs) in plasma-derived EVs were dysregulated in PE compared to normal pregnancy and display different temporal patterns during gestation.

METHODS

We isolated EVs from plasma at weeks 22-24 and 36-38 in women with and without PE (n=7 in each group) and performed RNA-seq, focusing on mRNAs and lncRNAs. We validated highly expressed mitochondrial and platelet-derived RNAs discovered from central pathways in 60 women with/without PE. We examined further one of the regulated RNAs, noncoding mitochondrially encoded tRNA alanine (MT-TA), in leukocytes and plasma to investigate its biomarker potential and association with clinical markers of PE.

RESULTS

We found abundant levels of platelet-derived and mitochondrial RNAs in EVs. Expression of these RNAs were decreased and lncRNAs increased in EVs from PE compared to without PE. These findings were further validated by qPCR for mitochondrial RNAs MT-TA, MT-ND2, MT-CYB and platelet-derived RNAs PPBP, PF4, CLU in EVs. Decreased expression of mitochondrial tRNA MT-TA in leukocytes at 22-24 weeks was strongly associated with the subsequent development of PE.

CONCLUSIONS

Platelet-derived and mitochondrial RNA were highly expressed in plasma EVs and were decreased in EVs isolated from women with PE compared to without PE. LncRNAs were mostly increased in PE. The MT-TA in leukocytes may be a useful biomarker for prediction and/or early detection of PE.

The Placenta in Congenital Heart Disease: Form, Function and Outcomes

The maternal-fetal environment, controlled and modulated by the placenta, plays a critical role in the development and well-being of the fetus, with long-term impact through programming of lifelong health. The fetal cardiovascular system and placenta emerge at the same time embryologically, and thus placental form and function are altered in the presence of congenital heart disease (CHD). In this review, we report on what is known about the placenta from a structural and functional perspective when there is CHD. We describe the various unique pathologic findings as well as the diagnostic imaging tools used to characterize placental function in utero. With growing interest in the placenta, a standardized approach to characterizing placental pathology has emerged. Furthermore, application of ultrasonography techniques and magnetic resonance imaging now allow for insights into placental blood flow and functionality in vivo. An improved understanding of the intriguing relationship between the placenta and the fetal cardiovascular system will provide opportunities to develop novel ways to optimize outcomes. Once better understood, therapeutic modulation of placental function offered during the vulnerable period of fetal plasticity may be one of the most impactful ways to alter the course of CHD and its complications.

Qatar population-specific centile charts of placental weight in 80 722 newborns: relation to maternal age, gestational age, newborn birth weight, and gender, between the 37 th and 42 nd weeks of gestation

BACKGROUND

Data about placental weight (PW) in relation to birth weight (BW) and gestational age (GA) are lacking in Arabic countries.

AIMS OF THE STUDY

(a) to find out the national PW standards for babies born between 37th and 42nd weeks of gestation in male and female babies born in Qatar; (b) to study the relation, if any, between PW and maternal age, gestational age (GA), birth weight (BW), and gender of the newborn.

MATERIALS AND METHODS

A National population-based retrospective chart review study was conducted between 1-2016 to 12-2019 (n = 80 722). Data of gestational age (GA) at delivery (in weeks), newborn birth weight (BW), PW, and gender at birth, were collected from singleton babies born between 37 th and 42nd weeks of gestation.

RESULTS

The PW ranged from 440 to 860 grams (g) with a mean of 682 ± 96 g. at term for boys and 673 ± 94 g. for girls. The mean BW was 3 036 ± 448 g and BW/PW ratio was 0.203 ± 0.026. The PW continued to increase through 41 weeks' gestation, in boys and girls with a significant decrease at the 42nd week of gestation. PW was significantly correlated with BW (r = 0.596, P: < 0.001) and GA (r = 0.15, P: <0.001) and accounted for 43.4% of the explained variability in birth weight.

CONCLUSIONS

PW was a significant predictor of BW with a consistent increase in PW until the 41st week of gestation in boys and girls and a positive correlation with BW and GA.

Relationship between the Central and Peripheral Thyroid Sensitivity Indices and Fetal Macrosomia: A Cohort Study of Euthyroid Pregnant Women in China

(1) Background: To explore the correlation between central and peripheral thyroid sensitivity indices and macrosomia in euthyroid pregnant women and to provide clinical basis for the prevention and treatment of macrosomia. (2) Methods: This study is a prospective study. A total of 1176 euthyroid women in early pregnancy in the obstetrics department of Peking University International Hospital from December 2017 to March 2019 were enrolled. The women were divided into two groups, namely the macrosomia and non-macrosomia groups, according to birth weight. (3) Results: The level of free triiodothyronine (FT3), thyroid-stimulating hormone (TSH), thyroid feedback quantile-based index (TFQI), thyrotropin-T4 resistance index (TT4RI), thyroid-stimulating hormone index (TSHI), and free triiodothyronine/free thyroxine (FT3/FT4) in the macrosomia group was higher than that in the non-macrosomia group (p < 0.05). The multivariate logistic regression model showed that FT3, TFQI, TT4RI, TSHI, and FT3/FT4 were independent risk factors for macrosomia in early pregnancy after adjusting for age, body mass index, parity, blood pressure, blood glucose, and blood lipid levels (p < 0.05, respectively). (4) Conclusions: TFQI, TT4RI, TSHI, and FT3/FT4 are independent risk factors for fetal macrosomia in early pregnancy in euthyroid women.

Associations between maternal dietary scores during early pregnancy with placental outcomes

Background and aims

Individual macronutrient and micronutrient effects on placental growth have been widely investigated. However, the influence of overall maternal diet is relatively unknown. Therefore, the aim of this study is to examine associations between a range of maternal dietary scores during early pregnancy with placental outcomes, and to investigate whether there is evidence of sexual dimorphism.

Methods

This analysis of the Lifeways Cross-Generational Cohort includes 276 mother-child pairs. A validated 148-item semi-quantitative food frequency questionnaire assessed maternal diet in early pregnancy. Dietary scores reflecting dietary quality [Healthy Eating Index (HEI-2015), Dietary Approaches to Stop Hypertension (DASH)], dietary inflammatory potential [Dietary Inflammatory Index (DII) and the energy adjusted DII (E-DII)], dietary antioxidant status [Dietary Antioxidant Quality (DAQ)], and glycemic and insulinemic loads/indices (GL/GI, IL/II) were calculated. Linear regression analyses assessed maternal dietary score relationships with untrimmed placental weight (PW) and birth weight:placental weight (BW:PW) ratio.

Results

In fully adjusted models, maternal E-DII and GI were positively associated, and HEI-2015 and DAQ were negatively associated with PW (B: 12.31, 95% CI: 0.41, 24.20, p = 0.04, B: 4.13, 95% CI: 0.10, 8.17, p = 0.04, B: -2.70, 95% CI: -5.03, -0.35, p = 0.02 and B: -15.03, 95% CI: -28.08, -1.98, p = 0.02, for E-DII, GI, HEI-2015 and DAQ respectively). Maternal DAQ associations with BW:PW ratio were attenuated. When stratified by sex, maternal GI and pregnancy-specific DAQ were associated with PW in female offspring (B: 5.61, 95% CI: 0.27, 10.96, p = 0.04 and B: -15.31, 95% CI: -30.35, -0.27, p = 0.046). Maternal E-DII and HEI-2015 were associated with PW in males (B: 24.31, 95% CI: 5.66, 42.96, p = 0.01 and B: -3.85, 95% CI: -7.47, -0.35, p = 0.03 respectively).

Conclusion

The results of this novel investigation suggest that maternal diet may influence placental development. Female fetuses may be more sensitive to increased glucose levels whereas male fetuses may be more susceptible to in-utero stresses that are regulated by inflammatory pathways and overall diet quality. Hence, early pregnancy offers an opportune time for a mother to prioritize dietary changes that focus on reducing inflammatory and glycemic responses.

Metabolic profiling of pregnancies complicated by preeclampsia: A longitudinal study

INTRODUCTION

Preeclampsia is associated with maternal metabolic disturbances, but longitudinal studies with comprehensive metabolic profiling are lacking. We aimed to determine metabolic profiles across gestation in women who developed preeclampsia compared with women with healthy pregnancies. We also explored the respective effects of body mass index (BMI) and preeclampsia on various metabolic measures.

MATERIAL AND METHODS

We measured 91 metabolites by high-throughput nuclear magnetic resonance spectroscopy at four time points (visits) during pregnancy (weeks 14-16, 22-24, 30-32 and 36-38). Samples were taken from a Norwegian pregnancy cohort. We fitted a linear regression model for each metabolic measure to compare women who developed preeclampsia (n = 38) and healthy controls (n = 70).

RESULTS

Among women who developed preeclampsia, 92% gave birth after 34 weeks of gestation. Compared to women with healthy pregnancies, women who developed preeclampsia had higher levels of several lipid-related metabolites at visit 1, whereas fewer differences were observed at visit 2. At visit 3, the pattern from visit 1 reappeared. At visit 4 the differences were larger in most subgroups of very-low-density lipoprotein particles, the smallest high-density lipoprotein, total lipids and triglycerides. Total fatty acids were also increased, of which monounsaturated fatty acids and saturated fatty acids showed more pronounced differences. Concentration of glycine tended to be lower in pregnancies with preeclampsia until visit 3, although this was not significant after correction for multiple testing. After adjustment for age, BMI, parity and gestational weight gain, all significant differences were attenuated at visits 1 and 2. The estimates were less affected by adjustment at visits 3 and 4.

CONCLUSIONS

In early pregnancy, the metabolic differences between preeclamptic and healthy pregnancies were primarily driven by maternal BMI, probably representing the women's pre-pregnancy metabolic status. In early third trimester, several weeks before clinical manifestation, the differences were less influenced by BMI, indicating preeclampsia-specific changes. Near term, women with preeclampsia developed an atherogenic metabolic profile, including elevated total lipids, very-low-density lipoprotein, triglycerides, and total fatty acids.

Joint Exposure to Ambient Air Pollutants Might Elevate the Risk of Small for Gestational Age (SGA) Infants in Wuhan: Evidence From a Cross-Sectional Study

Objective: To investigate the effect of exposure to multiple ambient air pollutants during pregnancy on the risk of children being born small for gestational age (SGA). Methods: An Air Pollution Score (APS) was constructed to assess the effects of being exposed to six air pollutants simultaneously, PM_2.5, PM₁₀, SO₂, NO₂, CO, and O₃ (referred to as joint exposure). A logistic regression model was applied to estimate the associations of APS and SGA. Results: The adjusted odds ratios (ORs) of SGA per 10 ug/m³ increased in APS during the first and second trimesters and the entire pregnancy were 1.003 [95% confidence intervals (CIs): 1.000, 1.007], 1.018 (1.012, 1.025), and 1.020 (1.009, 1.031), respectively. The ORs of SGA for each 10 μg/m³ elevated in APS during the whole pregnancy were 1.025 (1.005, 1.046) for mothers aged over 35 years old vs. 1.018 (1.005, 1.031) for mothers aged under 35 years old. Women who were pregnant for the first time were more vulnerable to joint ambient air pollution. Conclusion: In summary, the results of the present study suggested that joint exposure to ambient air pollutants was associated with the increment in the risks of SGA.

Maternal body mass index and placental weight: a role for fetal insulin, maternal insulin and leptin

PURPOSE

Placental weight (PW) has been found to mediate the main effect of maternal BMI on fetal size. Still, the BMI-PW association is poorly understood. Therefore, we aimed to explore potential explanatory variables, including gestational weight gain (GWG), early- and late-pregnancy circulating levels of maternal glucose, insulin, leptin, adiponectin, triglycerides, LDL-C, and HDL-C, and fetal insulin.

METHODS

We included two studies of pregnant women from Oslo University Hospital, Norway: the prospective STORK (n = 263) and the cross-sectional 4-vessel method study (4-vessel; n = 165). We used multiple linear regression for data analyses. A non-linear BMI-PW association was observed, which leveled off from BMI25. Therefore, BMI <25 and ≥25 were analyzed separately (n = 170/122 and 93/43 for STORK/4-vessel). Confounding variables included maternal age, parity, and gestational age.

RESULTS

PW increased significantly per kg m-2 only among BMI <25 (univariate model's std.β[p] = 0.233 [0.002] vs. 0.074[0.48]/0.296[0.001] vs. -0.030[0.85] for BMI <25 vs. ≥25 in STORK/4-vessel). Maternal early- but not late-pregnancy insulin and term fetal insulin were associated with PW. The estimated effect of early pregnancy insulin was similar between the BMI groups but statistically significant only among BMI <25 (std.β[p] = 0.182[0.016] vs. 0.203[0.07] for BMI <25 vs. ≥25). Late pregnancy leptin was inversely associated with PW with a 1.3/1.7-fold greater effect among BMI ≥25 than BMI <25 in the STORK/4-vessel.

CONCLUSIONS

The BMI-PW association was non-linear: an association was observed for BMI <25 but not for BMI ≥25. Leptin may be involved in the non-linear association through a placental-adipose tissue interplay. Maternal early pregnancy insulin and fetal insulin at term were associated with PW.

Coronavirus disease 2019 and the placenta: A literature review

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has been implicated in the clinical pathology of multiple organs and organ systems. Due to the novelty of the disease, there is a need to review emerging literature to understand the profile of SARS-CoV-2 in the placenta. This review sought to evaluate the literature on the mediators, mechanism of entry, pathogenesis, detection, and pathology of SARS-CoV-2 in the placenta. Systematic literature searches found 96 eligible studies. Our review revealed that SARS-CoV-2 canonical mediators, angiotensin-converting enzyme-2 (ACE2), and transmembrane serine protease-2 (TMPRSS2) are variably expressed in various placenta compartments, including the villous cytotrophoblasts, syncytiotrophoblasts (STBs), and extravillous trophoblasts (EVTs) throughout pregnancy. Placental SARS-CoV-2 and coronavirus-associated receptors and factors (SCARFs), including basigin (BSG/CD147), dipeptidyl peptidase-4 (DPP4/CD26), cathepsin B/L (CTL B/L), furin, interferon-induced transmembrane protein (IFITM1-3), and lymphocyte antigen 6E (LY6E) may increase or reduce the permissiveness of the placenta to SARS-CoV-2. EVTs express genes that code for proteins that may drive viral pathogenesis in the placenta. Viral RNA, proteins, and particles were detected primarily in the STBs by in situ hybridization, immunohistochemistry, electron microscopy, and polymerase chain reaction. Placental pathology in SARS-CoV-2-infected placentas included maternal and fetal vascular malperfusion and a generally nonspecific inflammatory-immune response. The localization of SARS-CoV-2 receptors, proteases, and genes involved in coding proteins that drive viral pathogenesis in the placenta predisposes the placenta to SARS-CoV-2 infection variably in all pregnancy trimesters, with antecedent placental pathology. There is a need for further studies to explicate the mechanism of entry and pathogenesis of SARS-CoV-2 in the placenta.

Placenta-derived proteins across gestation in healthy pregnancies-a novel approach to assess placental function?

BACKGROUND

Placenta-derived proteins in the systemic maternal circulation are suggested as potential biomarkers for placental function. However, the identity and longitudinal patterns of such proteins are largely unknown due to the inaccessibility of the human placenta and limitations in assay technologies. We aimed to identify proteins derived from and taken up by the placenta in the maternal circulation. Furthermore, we aimed to describe the longitudinal patterns across gestation of placenta-derived proteins as well as identify placenta-derived proteins that can serve as reference curves for placental function.

METHODS

We analyzed proteins in plasma samples collected in two cohorts using the Somalogic 5000-plex platform. Antecubital vein samples were collected at three time points (gestational weeks 14-16, 22-24, and 30-32) across gestation in 70 healthy pregnancies in the longitudinal STORK cohort. In the cross sectional 4-vessel cohort, blood samples were collected simultaneously from the maternal antecubital vein (AV), radial artery (RA), and uterine vein (UV) during cesarean section in 75 healthy pregnancies. Placenta-derived proteins and proteins taken up by the placenta were identified using venoarterial differences (UV-RA). Placenta-derived proteins were defined as placenta-specific by comparison to the venoarterial difference in the antecubital vein-radial artery (AV-RA). These proteins were described longitudinally based on the STORK cohort samples using a linear mixed effects model per protein. Using a machine learning algorithm, we identified placenta-derived proteins that could predict gestational age, meaning that they closely tracked gestation, and were potential read-outs of placental function.

RESULTS

Among the nearly 5000 measured proteins, we identified 256 placenta-derived proteins and 101 proteins taken up by the placenta (FDR < 0.05). Among the 256 placenta-derived proteins released to maternal circulation, 101 proteins were defined as placenta-specific. These proteins formed two clusters with distinct developmental patterns across gestation. We identified five placenta-derived proteins that closely tracked gestational age when measured in the systemic maternal circulation, termed a "placental proteomic clock."

CONCLUSIONS

Together, these data may serve as a first step towards a reference for the healthy placenta-derived proteome that can be measured in the systemic maternal circulation and potentially serve as biomarkers of placental function. The "placental proteomic clock" represents a novel concept that warrants further investigation. Deviations in the proteomic pattern across gestation of such proteomic clock proteins may serve as an indication of placental dysfunction.

An Investigation of the Relationship Between Dietary Patterns in Early Pregnancy and Maternal/Infant Health Outcomes in a Chinese Cohort

Background

Studies assessing links between maternal diet and pregnancy outcomes have focused predominantly on individual nutrients or foods. However, nutrients are typically consumed in combinations of foods or beverages (i.e., dietary patterns). Taking into account the diet as a whole appreciates that nutrient absorption and metabolism are influenced by other nutrients and the food matrix.

Objective

The aim of this study was to investigate the relationship between dietary pattern consumption in early pregnancy and pregnancy/infant outcomes, including gestational diabetes mellitus, gestational weight gain, preeclampsia, placental weight, gestational age at delivery, small-for-gestational-age, large-for-gestational-age, macrosomia, measures of infant body composition, and scores on two main indices of the Bayley Scales of Infant Development [Mental Development Index (MDI) and the Psychomotor Development Index (PDI)] at 12 months.

Design

Our study included 1,437 participants from a mother-infant cohort in Chongqing, China. Maternal diet was assessed using a 96-item food frequency questionnaire at 11–14 weeks gestation. Dietary patterns were constructed using principal component analysis. Multivariate regressions were performed to assess associations between maternal dietary pattern scores and pregnancy and infant outcomes, adjusting for confounders.

Results

Two dietary patterns were derived: a pattern high in pasta, sweetened beverages, and oils and condiments (PSO-based dietary pattern) and a pattern high in fish, poultry, and vegetables (FPV-based dietary pattern). Higher scores on the PSO-based dietary pattern were associated with lower infant standardized scores on the PDI of the Bayley Scales of Infant Development, β (95% confidence interval) = −1.276 (−2.392, −0.160); lower placental weight, β (95% CI) = −6.413 (−12.352g, −0.473); and higher infant's tricep skinfold thickness at 6 weeks of age. β (95% CI) = 0.279 (0.033, 0.526). Higher scores on the FPV-based dietary pattern were associated with higher gestational weight gain between visit 1 (11–14 week's gestation) and 3 (32–34 week's gestation). β (95% CI) = 25.612 (13.255, 37.969). No significant associations were observed between dietary pattern scores and the remaining pregnancy/infant outcomes investigated or MDI scores on the Bayley Scales of Infant Development. This was the first study to investigate the association between dietary patterns in early pregnancy and infant neurocognition in a Chinese cohort.

Mapping the Cord Blood Transcriptome of Pregnancies Affected by Early Maternal Anemia to Identify Signatures of Fetal Programming

CONTEXT

Anemia during early pregnancy (EP) is common in developing countries and is associated with adverse health consequences for both mothers and children. Offspring of women with EP anemia often have low birth weight, which increases risk for cardiometabolic diseases, including type 2 diabetes (T2D), later in life.

OBJECTIVE

We aimed to elucidate mechanisms underlying developmental programming of adult cardiometabolic disease, including epigenetic and transcriptional alterations potentially detectable in umbilical cord blood (UCB) at time of birth.

METHODS

We leveraged global transcriptome- and accompanying epigenome-wide changes in 48 UCB from newborns of EP anemic Tanzanian mothers and 50 controls to identify differentially expressed genes (DEGs) in UCB exposed to maternal EP anemia. DEGs were assessed for association with neonatal anthropometry and cord insulin levels. These genes were further studied in expression data from human fetal pancreas and adult islets to understand their role in beta-cell development and/or function.

RESULTS

The expression of 137 genes was altered in UCB of newborns exposed to maternal EP anemia. These putative signatures of fetal programming, which included the birth weight locus LCORL, were potentially mediated by epigenetic changes in 27 genes and associated with neonatal anthropometry. Among the DEGs were P2RX7, PIK3C2B, and NUMBL, which potentially influence beta-cell development. Insulin levels were lower in EP anemia-exposed UCB, supporting the notion of developmental programming of pancreatic beta-cell dysfunction and subsequently increased risk of T2D in offspring of mothers with EP anemia.

CONCLUSIONS

Our data provide proof-of-concept on distinct transcriptional and epigenetic changes detectable in UCB from newborns exposed to maternal EP anemia.

Assessment of pregnancy dietary intake and association with maternal and neonatal outcomes

BACKGROUND

Maternal dietary habits are contributors of maternal and fetal health; however, available data are heterogeneous and not conclusive.

METHODS

Nutrient intake during pregnancy was assessed in 503 women with uncomplicated pregnancies, using the validated Food Frequency Questionnaire developed by the European Prospective Investigation into Cancer and Nutrition (EPIC-FFQ).

RESULTS

In all, 68% of women had a normal body mass index at the beginning of pregnancy, and 83% of newborns had an appropriate weight for gestational age. Maternal pre-pregnancy body mass index (BMI), gestational weight gain (GWG), and placental weight were independently correlated with birth weight. GWG was not related to the pre-pregnancy BMI. EPIC-FFQ evaluation showed that 30% of women adhered to the European Food Safety Authority (EFSA) ranges for macronutrient intake. In most pregnant women (98.1%), consumption of water was below recommendations. Comparing women with intakes within EFSA ranges for macronutrients with those who did not, no differences were found in BMI, GWG, and neonatal or placental weight. Neither maternal nor neonatal parameters were associated with the maternal dietary profiles.

CONCLUSIONS

In our population, maternal pre-pregnancy BMI, GWG, and placental weight are determinants of birth weight percentile, while no association was found with maternal nutrition. Future studies should explore associations through all infancy.

IMPACT

Maternal anthropometrics and nutrition status may affect offspring birth weight. In 503 healthy women, maternal pre-pregnancy body mass index (BMI), gestational weight gain (GWG), and placental weight were independently correlated to neonatal birth weight. GWG was not related to the pre-pregnancy BMI. In all, 30% of women respected the EFSA ranges for macronutrients. Neither maternal nor neonatal parameters were associated with maternal dietary profiles considered in this study. Maternal pre-pregnancy BMI, GWG, and placental weight are determinants of neonatal birth weight percentile, while a connection with maternal nutrition profiles was not found.

Associations of maternal blood pressure-raising polygenic risk scores with fetal weight

Maternal blood pressure (BP) is associated with variations in fetal weight, an important determinant of neonatal and adult health. However, the association of BP-raising genetic risk with fetal weight is unknown. We tested the associations of maternal BP-raising polygenic risk scores (PRS) with estimated fetal weights (EFWs) at 13, 20, 27, and 40 weeks of gestation. This study included 622 White, 637 Black, 568 Hispanic, and 238 Asian pregnant women with genotype data from the NICHD Fetal Growth Studies. PRS of systolic (SBP) and diastolic BP (DBP) were calculated for each participant based on summary statistics from a recent genome-wide association study. Linear regression models were used to compare mean EFW differences between the highest versus lowest tertile of PRS, adjusting for maternal age, education, parity, genetic principal components and fetal sex. Hispanics in the highest DBP PRS tertile, compared to those in the lowest, had 8.1 g (95% CI: -15.1, -1.1), 32.4 g (-58.4, -6.4) and 119.4 g (-218.1, -20.7) lower EFW at 20, 27 and 40 weeks, respectively. Similarly, Asians in the highest DBP PRS tertile had 137.2 g (-263.5, -10.8) lower EFW at week 40, and those in the highest tertile of SBP PRS had 3.2 g (-5.8, -0.7), 12.9 g (-23.5, -2.4), and 39.8 g (-76.9, -2.7) lower EFWs at 13, 20, and 27 weeks. The findings showed that pregnant women's genetic susceptibility to high BP contributes to reduced fetal growth, suggesting a potential future clinical application in perinatal health.

Investigation of HoxB3 and Growth Factors Expression in Placentas of Various Gestational Ages

An evaluation of transforming growth factor beta (TGFβ), hepatocyte growth factor (HGF), basic fibroblast growth factor (FGF-2), fibroblast growth factors receptor 1 (FGFR1) and Hox-positive cells in the human placenta, and their correlation with gestational time at delivery and pregnancy outcomes, may provide not only a better understanding of the role of Hox genes and growth factors in human development, but also may be of clinical importance in reproductive medicine. This study analyzed the immunohistochemical identification of TGFβ, HGF, FGF-2, FGFR1 and HoxB3 in placentas of various gestational ages. We found few (+) TGFβ, moderate (++) FGF-2 and numerous (+++) HGF and FGFR1 positive structures. Occasional (0/+) to numerous (+++) HoxB3-positive structures were detected in different types of placental cells specifically, cytotrophoblasts, syncytiotrophoblast, extravillous trophoblasts, and Höfbauer cells. Correlating the appearance of HoxB3 staining in placentas with neonatal parameters, we found a statistically significant negative correlation with ponderal index (r = −0.323, p = 0.018) and positive correlation with neonate body length (r = 0.541, p = 0.046). The number of HoxB3-positive cells did not correlate with growth factors and gestational age, but with neonatal anthropometrical parameters, indicating the role of HoxB3 not only in placental development, but also in the longitudinal growth of the fetus. TGFβ and FGF-2 did not play a significant role in the development of the placenta beyond 22nd week of pregnancy, while HGF and FGFR1 immunoreactive cells increased with advancing gestation, indicating increasingly evolving maturation (growth, proliferation) of the placenta, especially in the third trimester.

Placenta mediates the effect of maternal hypertension polygenic score on offspring birth weight: a study of birth cohort with fetal growth velocity data

BACKGROUND

Low birth weight (LBW) and fetal growth restriction are associated with the development of cardio-metabolic diseases later in life. A recent Mendelian randomization study concluded that the susceptibility of LBW infants to develop hypertension during adulthood is due to the inheritance of hypertension genes from the mother and not to an unfavorable intrauterine environment. Therein, a negative linear association has been assumed between genetically estimated maternal blood pressure (BP) and birth weight, while the observed relationship between maternal BP and birth weight is substantially different from that assumption. As many hypertension genes are likely involved in vasculature development and function, we hypothesized that BP-increasing genetic variants could affect birth weight by reducing the growth of the placenta, a highly vascular organ, without overtly elevating the maternal BP.

METHODS

Using a birth cohort in the Japanese population possessing time-series fetal growth velocity data as a target and a GWAS summary statistics of BioBank Japan as a base data, we performed polygenic score (PGS) analyses for systolic BP (SBP), diastolic BP, mean arterial pressure, and pulse pressure. A causal mediation analysis was performed to assess the meditation effect of placental weight on birth weight reduced by maternal BP-increasing PGS. Maternal genetic risk score constituted of only "vasculature-related" BP single nucleotide polymorphisms (SNPs) was constructed to examine the involvement of vascular genes in the mediation effect of placental weight. We identified gestational week in which maternal SBP-increasing PGS significantly decreased fetal growth velocity.

RESULTS

We observed that maternal SBP-increasing PGS was negatively associated with offspring birth weight. A causal mediation analysis revealed that a large proportion of the total maternal PGS effect on birth weight was mediated by placental weight. The placental mediation effect was remarkable when genetic risk score was constituted of "vasculature-related" BP SNPs. The inverse association between maternal SBP PGS and fetal growth velocity only became apparent in late gestation.

CONCLUSIONS

Our study suggests that maternal hypertension genes are strongly associated with placental growth and that fetal growth inhibition is induced through the intrauterine environment established by the placenta.

The effects of exercise during pregnancy on placental composition: A systematic review and meta-analysis

INTRODUCTION

Morphological changes to the placenta occur as the demands of the foetus increase throughout gestation. Physical activity during pregnancy is known to benefit both the mother and infant, however the impact of antenatal exercise training on placental development is less known. The aim of this systematic review and meta-analysis was to investigate the effects of exercise training during pregnancy on measures of placental composition.

METHODS

Six electronic databases were searched from inception to June 2021 for studies comparing regular antenatal exercise with either usual maternal care or no exercise for its effect on measures of placental morphological composition. Meta-analyses were performed for placental weight and the placental weight to birthweight (PWBW) ratio.

RESULTS

Seven randomised controlled trials and two cohort studies were included in the systematic review and meta-analysis (n = 9). There was no significant difference in placental weight (mean difference (MD) = -9.07g, p = 0.42) or the PWBW ratio (MD = 0.00, p = 0.32) between exercise and control groups. Parenchymal tissue volume was higher, represented by an increase in villous tissue, and non-parenchymal volume was lower in women who exercised regularly compared to those that were not exercising during pregnancy.

DISCUSSION

Exercise training during pregnancy may not alter placental weight or the PWBW ratio. However, findings from this review indicate that antenatal exercise training can promote advantageous morphological changes to placental tissues.

Dysregulated non-coding telomerase RNA component and associated exonuclease XRN1 in leucocytes from women developing preeclampsia-possible link to enhanced senescence

Senescence in placenta/fetal membranes is a normal phenomenon linked to term parturition. However, excessive senescence which may be induced by telomere attrition, has been associated with preeclampsia (PE). We hypothesized that the telomerase complex in peripheral blood mononuclear cells (PBMC) and circulating telomere associated senescence markers would be dysregulated in women with PE. We measured long non-coding (nc) RNA telomerase RNA component (TERC) and RNAs involved in the maturation of TERC in PBMC, and the expression of TERC and 5′–3′ Exoribonuclease 1 (XRN1) in extracellular vesicles at 22–24 weeks, 36–38 weeks and, 5-year follow-up in controls and PE. We also measured telomere length at 22–24 weeks and 5-year follow-up. The circulating senescence markers cathelicidin antimicrobial peptide (CAMP), β-galactosidase, stathmin 1 (STMN1) and chitotriosidase/CHIT1 were measured at 14–16, 22–24, 36–38 weeks and at 5-year follow-up in the STORK study and before delivery and 6 months post-partum in the ACUTE PE study. We found decreased expression of TERC in PBMC early in pregnant women who subsequently developed PE. XRN1 involved in the maturation of TERC was also reduced in pregnancy and 5-year follow-up. Further, we found that the senescence markers CAMP and β-galactosidase were increased in PE pregnancies, and CAMP remained higher at 5-year follow-up. β-galactosidase was associated with atherogenic lipid ratios during pregnancy and at 5-year follow-up, in PE particularly. This study suggests a potential involvement of dysfunctional telomerase biology in the pathophysiology of PE, which is not restricted to the placenta.

Association between prenatal phthalate exposure and anthropometric measures of newborns in a sample of Iranian population

Phthalates or phthalic acid esters (PAEs) are a group of compounds which they can be entered into the human body through the various pathways. The aim of this study was to examine associations between prenatal phthalates exposure with anthropometric measures of neonates. Urine samples were obtained from 121 Iranian pregnant women at their first trimester of pregnancy, and the levels of monobutyl phthalate (MBP), mono-benzyl phthalate (MBzP), mono-2-ethylhexyl phthalate (MEHP), and mono (2-ethyl-5hydroxyhexyl) phthalate (MEHHP) metabolites were determined by gas chromatography mass spectrometry (GC/MS). The correlations between the maternal urinary concentrations of phthalate metabolites with anthropometric measures of neonates as well as with the socio-demographic factors of participants (maternal education, age, family income, pre-pregnancy body mass index), their lifestyle variables (smoking habit, food pattern, and physical activity), and use of cleaning products (cosmetic and household cleaning products) were investigated. MBzP, MBP, MEHP, and MEHHP were detected in 100% of the participants with the concentration ranged 120 to 860 μg/g creatinine. Significant correlations were observed between the urinary levels of maternal MBzP (adjusted β = 0.3 (0.001), p = 0.03) and MEHHP (adjusted β = 0.3 (0.001), p = 0.04) with the birth weight of female neonates. MBP (adjusted β = -0.3 (0.02), p = 0.04) and MBzP (adjusted β = -0.3 (0.001), p = 0.02) had negative associations with the head circumference in male and female newborns, respectively. Furthermore, plastic packaging for pickle and passive smoking during pregnancy were identified to be significantly associated with low birth weight (p value < 0.05). Iranian pregnant women had higher concentrations of urinary phthalates compared to the other countries. Based on the findings, the higher prenatal exposure to phthalates could adversely impact the health status of newborns.

Mood instability, depression, and anxiety in pregnancy and adverse neonatal outcomes

Background

Antenatal women experience an increased level of mood and anxiety symptoms, which have negative effects on mothers’ mental and physical health as well as the health of their newborns. The relation of maternal depression and anxiety in pregnancy with neonate outcomes is well-studied with inconsistent findings. However, the association between antenatal mood instability (MI) and neonatal outcomes has not been investigated even though antenatal women experience an elevated level of MI. We sought to address this gap and to contribute to the literature about pregnancy neonate outcomes by examining the relationship among antenatal MI, depression, and anxiety and neonatal outcomes.

Methods

A prospective cohort of women (n = 555) participated in this study at early pregnancy (T1, 17.4 ± 4.9 weeks) and late pregnancy (T2, 30.6 ± 2.7 weeks). The Edinburgh Postnatal Depression Scale (EPDS) was used to assess antenatal depressive symptoms, anxiety was measured by the EPDS anxiety subscale, and mood instability was measured by a visual analogue scale with five questions. These mood states together with stress, social support, as well as lifestyle were also examined in relation to neonatal outcomes using chi-square tests and logistic regression models.

Results

Mood instability, depression, and anxiety were unrelated to adverse neonatal outcomes. Only primiparous status was associated with small for gestational age after Bonferroni correction.

Conclusions

We report no associations between antenatal mood symptoms including MI, depression, and anxiety and neonatal outcomes. More studies are required to further explore the relationship between antenatal mood instability, depression, and anxiety and neonatal outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04021-y.

No impact of gestational diabetes mellitus on pregnancy complications in women with PCOS, regardless of GDM criteria used

Polycystic ovary syndrome (PCOS) is characterized by the presence of insulin resistance, and women with PCOS have high prevalence of gestational diabetes (GDM). Both conditions have been associated with increased risk for pregnancy complications such as preterm birth, preeclampsia and increased offspring birth weight. We aimed to estimate the prevalence of GDM in women with PCOS using both previous and new diagnostic criteria, and to analyse whether the risk of pregnancy complications increased with the presence of GDM. In addition, we aimed to assess the response to metformin treatment in PCOS women with GDM. We performed post-hoc analysis of three prospective, double blinded studies of altogether 791 pregnant women with PCOS randomized to either metformin or placebo treatment from first trimester to delivery. Glucose data allowing GDM classification after previous (WHO 1999) and new (WHO 2013 and Norwegian 2017) diagnostic criteria were available for 722 of the women. Complications such as preeclampsia, late miscarriage and preterm birth, birth weight and gestational age were correlated to the presence of GDM and metformin treatment. The prevalence of GDM was 28.3% (WHO 1999), 41.2% (WHO 2013) and 27.2% (Norwegian 2017). Having GDM already in first trimester associated with increased risk for late miscarriage (p<0.01). Having GDM according to newer criteria correlated to increased maternal age and BMI (p<0.001). Otherwise, having GDM (any criteria) correlated neither to the development of preeclampsia, nor to birth weight z-score or the proportion of offspring being large for gestational weight. Maternal age and BMI, parity and gestational weight gain, but not GDM or metformin treatment, were determinants for birth weight z-score. Conclusion: in pregnant women with PCOS, having GDM did not increase the risk for other pregnancy complications except for an increased risk for late miscarriage among those with GDM already in the first trimester.

Placental weight mediates association between prenatal exposure to cooking oil fumes and preterm birth

Background: There are some reports on association between maternal prenatal cooking oil fume (COF) exposure and preterm birth (PTB), but its mechanism remains poorly understood. Therefore, this study aims to assess whether placental weight mediates their associations.Method: We enrolled 619 pregnant women delivering PTB newborns as cases and 1701 delivering full-term appropriate for gestational age newborns as controls. They were inquired with a self-reported questionnaire about prenatal COF exposure, socio-demographics and obstetric characteristics at Women and Children's Hospitals of Shenzhen and Foshan. After controlling for the potential confounders, a series of logistic and linear regressions were conducted to assess associations among COF exposure, placental weight and PTB, and the mediation of placental weight in the association between COF exposure and PTB.Results: Maternal prenatal COF exposure was significantly associated with PTB and the frequency of prenatal COF exposure was negatively associated with placental weight. Compared with mother who never cooked, those cooking occasionally, sometimes or often increased the risk of PTB, and similarly, those cooking between half to an hour was also showed a higher risk of PTB. Typical Chinese cooking methods including stir-frying, pan-frying and deep-frying were also associated with PTB. Different oil types mainly used, including peanut oil, corn oil and animal oil were associated with PTB as well. Mediation analysis illustrated that placental weight partially mediated 13.60% (95% CI = 10.62-33.20%) of the effects on the association between the frequency of maternal prenatal COF exposure and PTB.Conclusion: Maternal cooking during pregnancy and the frequency of prenatal COF exposure might increase the risk of PTB, in which placenta might play mediation role.

The Mediating Role of Placental Weight Change in the Association Between Prenatal Exposure to Thallium and Birth Weight: A Prospective Birth Cohort Study

Background: Previous studies have demonstrated the embryotoxicity and fetotoxicity of thallium (Tl). However, the effects of prenatal exposure to Tl on birth weight and placental weight and the mediating role of placental weight in the association of Tl with birth weight remain unclear.

Methods: We recruited 2,748 participants from the ongoing Prenatal Environment and Offspring Health Cohort (PEOH Cohort) study, which was initiated in 2016 in Guangzhou, China. The Tl concentrations in maternal urine samples collected during the first and third trimester were determined by inductively coupled plasma mass spectrometry. Birth weight and placental weight were extracted from maternal medical records.

Results: Pregnant women exposed to the highest tertile of Tl in the first trimester (β = −42.7 g, 95% CI: −82.3, −3.1 g) and third trimester (β = −50.6 g, 95% CI: −99.0, −2.3 g) had babies with lower birth weights than those exposed to the lowest tertile. We also found significant negative associations of exposure to Tl concentrations in the first and third trimester with placental weight. Mediation analyses showed that 50.3% (95% CI: 15.9, 79.2%) and 33.5% (95% CI: 1.3, 80.3%) of the effects of Tl exposure in the first and third trimester on birth weight were mediated by decreased placental weight.

Conclusion: Our results suggest that prenatal exposure to Tl is negatively associated with birth weight and that this association may be mediated by decreased placental weight.

Association of Elevated Maternal Serum Total Bile Acids With Low Birth Weight and Intrauterine Fetal Growth Restriction

IMPORTANCE

Bile acids play essential roles in metabolic modulation. Excessive serum total bile acid (sTBA) levels during pregnancy are associated with adverse perinatal outcomes; however, their association with the risk of intrauterine growth restriction (IUGR) remains unclear.

OBJECTIVE

To investigate the association between maternal sTBA concentration during pregnancy and the risk of IUGR.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included pregnant individuals who delivered live singleton neonates and had regular antenatal examination records available at a hospital-based center in Shanghai, China, from 2014 to 2018. Data were analyzed from July to November 2020.

EXPOSURES

Maternal sTBA concentration during pregnancy.

MAIN OUTCOMES AND MEASURES

Fetal birth weight and probability of low birth weight (LBW) and IUGR.

RESULTS

This study included 68 245 singleton pregnancies with live births for analysis. The mean (SD) age of the pregnant individuals was 30.5 (3.8) years, 67 168 patients (98.4%) were Han, and 50 155 (73.5%) were nulliparous. Nonlinear regression models suggested that there was an inverted J-shaped association between maternal sTBA level during pregnancy and fetal birth weight, with a steep decrease in birth weight at high sTBA levels (estimated mean [SE] birth weight for sTBA of 40.8 ug/mL, 2879 [39.9] g) and greater birth weights at lower sTBA levels (estimated mean [SE] birth weight for sTBA 0.4 μg/mL, 3290 [3.9] g; and for 4.1 μg/mL, 3334 [1.6] g). Lower birth weight and a higher incidence of IUGR were observed in patients with gestational hypercholanemia (sTBA ≥4.08 μg/mL) compared with those without gestational hypercholanemia (birth weight: estimated adjusted mean [SE], 3309 [3.32] vs 3338 [0.80] g; P = .005; incidence of IUGR: 62 of 4467 [1.4%] vs 312 of 63 778 [0.5%]; P < .001). Moreover, compared with patients with sTBA concentrations of less than 4.08 μg/mL, those with gestational hypercholanemia had an increased risk of LBW (adjusted odds ratio [aOR], 1.29; 95% CI, 1.09-1.53) and IUGR (aOR, 2.18; 95% CI, 1.62-2.91). In addition, there was an additive interaction between hypertensive disorders in pregnancy (HDP) and hypercholanemia on LBW and IUGR risk. The highest risks of LBW and IUGR were found in pregnant individuals with both HDP and hypercholanemia compared with those with normotensive pregnancies with sTBA concentrations less than 4.08 μg/mL (LBW: aOR, 9.13; 95% CI, 6.88-12.12; IUGR: aOR, 19.14; 95% CI, 12.09-30.28).

CONCLUSIONS AND RELEVANCE

This study found that gestational hypercholanemia was associated with an increased risk of LBW and IUGR, especially in pregnant individuals with HDP. Therefore, it would be meaningful to monitor sTBA concentration during the follow-up of pregnancies with potential IUGR.

Mediators Linking Maternal Weight to Birthweight and Neonatal Fat Mass in Healthy Pregnancies

CONTEXT

Lifestyle interventions have not efficaciously reduced complications caused by maternal weight on fetal growth, requiring insight into explanatory mediators.

OBJECTIVE

We hypothesized that maternal mediators, including adiponectin, leptin, insulin, and glucose, mediate effects of pregestational BMI (pBMI) and gestational weight gain (GWG) on birthweight and neonatal fat mass percentage (FM%) through placental weight and fetal mediators, including insulin levels (Ifv) and venous-arterial glucose difference (ΔGfva). Hypothesized confounders were maternal age, gestational age, and parity.

METHODS

A cross-sectional study of healthy mother-offspring-pairs (n = 165) applying the 4-vessel in vivo sampling method at Oslo University Hospital, Norway. We obtained pBMI, GWG, birthweight, and placental weight. FM% was available and calculated for a subcohort (n = 84). We measured circulating levels of adiponectin, leptin, glucose, and insulin and performed path analysis and traditional mediation analyses based on linear regression models.

RESULTS

The total effect of pBMI and GWG on newborn size was estimated to be 30 g (range, 16-45 g) birthweight and 0.17 FM% (range, 0.04-0.29 FM%) per kg∙m-2 pBMI and 31 g (range, 18-44 g) and 0.24 FM% (range, 0.10-0.37 FM%) per kg GWG. The placental weight was the main mediator, mediating 25-g birthweight and 0.11 FM% per kg∙m-2 pBMI and 25-g birthweight and 0.13 FM% per kg GWG. The maternal mediators mediated a smaller part of the effect of pBMI (3.8-g birthweight and 0.023 FM% per kg∙m-2 pBMI) but not GWG.

CONCLUSION

Placental weight was the main mediator linking pBMI and GWG to birthweight and FM%. The effect of pBMI, but not GWG, on birthweight and FM%, was also mediated via the maternal and fetal mediators.

Prenatal metal mixtures and fetal size in mid-pregnancy in the MADRES study

BACKGROUND

Fetal growth is predictive of health later in life. Both toxic and essential metals influence fetal growth, but most studies have focused on these elements individually and used birth weight as an indicator of fetal growth. The objective of the current study was to investigate the impact of a mixture of metals on fetal size in mid-pregnancy in a predominately lower income Hispanic pregnancy cohort in Los Angeles.

METHODS

For our primary analysis, we focused on six elements that have previously been associated individually with fetal size, including arsenic (As), barium (Ba), cadmium (Cd), mercury (Hg), molybdenum (Mo), and tin (Sn), measured in maternal urine samples collected in early pregnancy (median: 12.4 weeks gestation). In an exploratory analysis, we additionally included cobalt (Co), nickel (Ni), antimony (Sb), and thallium (Tl). Using covariate-adjusted Bayesian Kernel Machine Regression (BKMR) as our main mixture modeling approach, we examined the impact of these metals on fetal biometry measures obtained between 18 and 22 weeks gestation, with a focus on estimated fetal weight (EFW).

RESULTS

BKMR identified Mo and Ba as the mixture components that contributed most to associations with EFW. Linear associations were observed for both metals. An increase in Mo from the 25th to 75th percentile was associated with a 0.114 (95% credible interval (CI): 0.019, 0.247) SD higher EFW, equivalent to a 7.4 g difference. Similar associations were observed between Mo and the other fetal measures evaluated. In contrast, an increase in Ba from the 25th to 75th percentile was associated with a -0.076 (95% CI: 0.217, 0.066) SD lower EFW, equivalent to a 4.9 g difference. Similar inverse associations were observed for Ba in relation to abdominal circumference and biparietal diameter. BKMR also identified a possible interaction between Ba and Mo in relation to head circumference, suggesting that the positive associations between Mo and this outcome may be attenuated at high levels of Ba, which was consistent with findings from linear regression (P_interaction = 0.03). In an exploratory analysis accounting for a larger mixture of metals, Mo and Ba consistently contributed most to associations with EFW. An inverse association was also identified between Sb and EFW.

CONCLUSIONS

Our results suggest that Mo may promote fetal growth, while Ba and Sb may reduce fetal growth, in this population.

Low CETP activity and unique composition of large VLDL and small HDL in women giving birth to small-for-gestational age infants

Cholesteryl ester transfer protein (CETP) regulates high density lipoproteins (HDL)-cholesterol (C) and HDL-C is essential for fetal development. We hypothesized that women giving birth to large-for-gestational-age (LGA) and small-for-gestational age (SGA) infants differed in longitudinal changes in lipoproteins, CETP activity and HDL-C and that placentas from women with higher or lower circulating HDL-C displayed differential expression of mRNAs involved in cholesterol/nutrient transport, insulin signaling, inflammation/ extracellular matrix (ECM) remodeling. Circulating lipids and CETP activity was measured during pregnancy, NMR lipidomics in late pregnancy, and associations with LGA and SGA infants investigated. RNA sequencing was performed in 28 placentas according to higher and lower maternal HDL-C levels. Lipidomics revealed high triglycerides in large VLDL and lipids/cholesterol/cholesteryl esters in small HDL in women giving birth to SGA infants. Placentas from women with higher HDL-C had decreased levels of CETP expression which was associated with mRNAs involved in cholesterol/nutrient transport, insulin signaling and inflammation/ECM remodeling. Both placental and circulating CETP levels were associated with growth of the fetus. Low circulating CETP activity at 36–38 weeks was associated with giving birth to SGA infants. Our findings suggest a link between increased maternal HDL-C levels, low CETP levels both in circulation and placenta, and SGA infants.

Peroxisome Proliferator-Activated Receptors (PPAR), fatty acids and microRNAs: Implications in women delivering low birth weight babies

Low birth weight (LBW) babies are associated with neonatal morbidity and mortality and are at increased risk for noncommunicable diseases (NCDs) in later life. However, the molecular determinants of LBW are not well understood. Placental insufficiency/dysfunction is the most frequent etiology for fetal growth restriction resulting in LBW and placental epigenetic processes are suggested to be important regulators of pregnancy outcome. Early life exposures like altered maternal nutrition may have long-lasting effects on the health of the offspring via epigenetic mechanisms like DNA methylation and microRNA (miRNA) regulation. miRNAs have been recognized as major regulators of gene expression and are known to play an important role in placental development. Angiogenesis in the placenta is known to be regulated by transcription factor peroxisome proliferator-activated receptor (PPAR) which is activated by ligands such as long-chain-polyunsaturated fatty acids (LCPUFA). In vitro studies in different cell types indicate that fatty acids can influence epigenetic mechanisms like miRNA regulation. We hypothesize that maternal fatty acid status may influence the miRNA regulation of PPAR genes in the placenta in women delivering LBW babies. This review provides an overview of miRNAs and their regulation of PPAR gene in the placenta of women delivering LBW babies.Abbreviations: AA - Arachidonic Acid; Ago2 - Argonaute2; ALA - Alpha-Linolenic Acid; ANGPTL4 - Angiopoietin-Like Protein 4; C14MC - Chromosome 14 miRNA Cluster; C19MC - Chromosome 19 miRNA Cluster; CLA - Conjugated Linoleic Acid; CSE - Cystathionine γ-Lyase; DHA - Docosahexaenoic Acid; EFA - Essential Fatty Acids; E2F3 - E2F transcription factor 3; EPA - Eicosapentaenoic Acid; FGFR1 - Fibroblast Growth Factor Receptor 1; GDM - Gestational Diabetes Mellitus; hADMSCs - Human Adipose Tissue-Derived Mesenchymal Stem Cells; hBMSCs - Human Bone Marrow Mesenchymal Stem Cells; HBV - Hepatitis B Virus; HCC - Hepatocellular Carcinoma; HCPT - Hydroxycamptothecin; HFD - High-Fat Diet; Hmads - Human Multipotent Adipose-Derived Stem; HSCS - Human Hepatic Stellate Cells; IUGR - Intrauterine Growth Restriction; LA - Linoleic Acid; LBW - Low Birth Weight; LCPUFA - Long-Chain Polyunsaturated Fatty Acids; MEK1 - Mitogen-Activated Protein Kinase 1; MiRNA - MicroRNA; mTOR - Mammalian Target of Rapamycin; NCDs - NonCommunicable Diseases; OA - Oleic Acid; PASMC - Pulmonary Artery Smooth Muscle Cell; PLAG1 - Pleiomorphic Adenoma Gene 1; PPAR - Peroxisome Proliferator-Activated Receptor; PPARα - PPAR alpha; PPARγ - PPAR gamma; PPARδ - PPAR delta; pre-miRNA - precursor miRNA; RISC - RNA-Induced Silencing Complex; ROS - Reactive Oxygen Species; SAT - Subcutaneous Adipose Tissue; WHO - World Health Organization.

Admixture mapping identifies African and Amerindigenous local ancestry loci associated with fetal growth

Fetal growth is an important determinant of cardiometabolic disease risk during childhood and adulthood. The genetic architecture of fetal growth remains largely understudied in ancestrally diverse populations. We conducted genome-wide admixture mapping scan and analysis of genetic ancestry among Hispanic American, African American, European American, and Asian American pregnant women to identify genetic loci associated with fetal growth measures across 13-40 weeks gestation. Fetal growth measures were associated with genome-wide average African, European, Amerindigenous and East Asian ancestry proportions (P ranged from10^-3 to 4.8 × 10^-2). Admixture mapping analysis identified ten African ancestry loci and three Amerindigenous ancestry loci significantly associated with fetal growth measures at Bonferroni-corrected levels of significance (P ranged from 2.18 × 10^-8 to 3.71 × 10^-6). At the chr2q23.3-24.2 locus in which higher African ancestry was associated with long bone (femur and humerus) lengths, the T allele of rs13030825 (GALNT13) was associated with longer humerus length in African Americans (β = 0.44, P = 6.25 × 10^-6 at week 27; β = 0.39, P = 7.72 × 10^-5 at week 40). The rs13030825 SNP accounted for most of the admixture association at the chr2q23.3-24.2 locus and has substantial allele frequency difference between African and European reference samples (F_ST = 0.55, P = 0.03). Regulatory annotation shows that rs13030825 overlaps with the serum response factor (SRF) transcription factor previously implicated in postnatal bone development of mice. Overall, we identified ancestry-related maternal genetic loci that influence fetal growth, shedding light on molecular pathways that regulate fetal growth and potential effects on health across the lifespan.Clinical trials registration ClinicalTrials.gov, NCT00912132.

Proportionality of Clinical Outcome and Placental Changes to the Increasing Severity of Maternal Hypertension- An Observational Study

OBJECTIVE

Preeclampsia and eclampsia remain the major causes of maternal and perinatal mortality and morbidity worldwide, causing 12-15% of direct maternal deaths. Although preeclampsia and related hypertensive disorders of pregnancy continue to affect 8% of all pregnancies, the incidence of preeclampsia has increased 40% in recent years. This study was carried out to analyse the different placental lesions and fetal outcome in different grades of maternal hypertension and to see if there is a linear relationship of the same.

MATERIAL AND METHOD

A total of 539 placenta specimens received at the department of Pathology from October 2017 to March 2019 were collected after obtaining informed consent. Of the 539 placentas, 87 hypertensive cases were graded and grouped according to the severity as gestational hypertension, mild preeclampsia, severe preeclampsia, eclampsia, and chronic hypertension and compared with 88 normotensive cases. The gross and microscopic findings were tabulated and analysed using the Statistical Package for the Social Sciences (SPSS) software.

RESULTS

Incidence of fetal death and growth restriction increased with increasing grade of maternal hypertension (p= 0.001). Abnormal shape of placenta (p= 0.034) and abnormal umbilical cord insertion (p= 0.028) were seen significantly more in the hypertensive group than in the normotensive group. Infarct and abnormal vasculo-syncytial membrane (p < 0.05) and abnormal villous maturation (p= 0. 039) were significantly increased in the hypertensive group than the normotensive group.

CONCLUSION

The incidence of adverse fetal outcome and placental changes suggestive of feto-maternal malperfusions shows a proportional trend with the increasing grade of maternal hypertension.

Consequences of Iodine Deficiency and Excess in Pregnancy and Neonatal Outcomes: A Prospective Cohort Study in Rio de Janeiro, Brazil

Background: Insufficient or excessive iodine intake during gestation may compromise adaptive mechanisms in maternal thyroid function and lead to adverse pregnancy outcomes. In this context, we aimed to study the effects of maternal iodine status in the first and third trimesters of gestation on obstetric and neonatal outcomes in an iodine-sufficient population in Rio de Janeiro, Brazil. Methods: A total of 214 pregnant women in the first trimester of gestation were enrolled and prospectively followed until delivery between 2014 and 2017. All participants were ≥18 and ≤35 years, had a spontaneous single pregnancy, and had no history of thyroid or other chronic diseases, nor were they taking iodine-containing supplements at enrollment. In the first trimester, we obtained clinical information and determined thyroid function and the urinary iodine concentration (UIC) of the participants. Thyroid function and UIC were reassessed in the third trimester. Iodine status was determined by the median of UIC obtained from six urine spot samples by the inductively coupled plasma mass spectrometry method. Pregnancy and neonatal outcomes and delivery information were obtained from medical records. Results: The median UIC in the whole population was 219.7 μg/L. The prevalence of UIC <150 μg/L was 17.2%, and 38.7% had UIC ≥250 μg/L. Gestational diabetes (GDM) was higher in the group with UIC 250-499 μg/L (n = 77) compared with the group with UIC 150-249 μg/L (n = 94) (20.3% vs. 9.7%, p < 0.05). Ultimately, UIC ≥250 μg/L was an independent risk factors for GDM (relative risk [RR] = 2.9 [confidence interval, CI = 1.1-7.46], p = 0.027) and hypertensive disorders of pregnancy (HDP) (RR = 4.6 [CI = 1.1-18.0], p = 0.029). Among 196 live-born newborns, lower birth length was observed in infants whose mothers had UIC <150μg/L (n = 37) in the first trimester compared with those with UIC 150-249 μg/L (n = 86) (median interquartile range: 48.0 [2.2] vs. 49.0 [4.0] cm, p = 0.01). Maternal UIC <150 μg/L was negatively associated with birth length of newborns (Exp (B) = 0.33 [CI = 0.1-0.9], p = 0.03). Conclusions: In a population whose median iodine intake is sufficient, extensive individual variation occurs. Such abnormalities are associated with increased GDM and HDP when UIC is ≥250 μg/L, and lower infant birth length when UIC is <150 μg/L.

Is small placenta a risk for low birth weight in KOKAN? (Data from a coastal region in the state of Maharashtra, India)

KOKAN region is characterized by undernutrition across all stages of lifecycle. Developmental Origins of Health & Disease hypothesis suggests that environmental influences in the early period of growth and development can contribute to the risks of noncommunicable diseases (NCD) in adulthood. Newborns and placentas of 815 pregnant mothers delivered in a rural hospital were studied. We tested the hypothesis that low placental weight will be associated with low birth weight (LBW). Mothers had a mean age of 26 years and were smaller in size at delivery [mean height of 152.1 cm (±6.1 cm), weight 52 kg (±10.2 kg), body mass index (BMI) 22.5 kg/m2 (±4.1 kg/m2)]. Mean placental weight was 488 g (±120 g). Mean birth weight, length, and head circumference of the newborn were 2.54 kg (±0.5 kg), 46.3 cm (±3.1 cm), and 32.7 cm (±1.7 cm), respectively. Prevalence of LBW, stunting, and small head size was 41.6%, 42.2%, and 18.2%, respectively. Maternal height, weight, and BMI at delivery were all positively associated with placental weight (p < 0.01 for all). Mothers with placentas in the lowest placental weight tertile had an increased likelihood of producing an LBW baby [OR 7.7, 95% CI (5.0, 11.8)], a stunted baby [OR 1.9 (1.4, 2.9)], or a baby with a small head circumference [OR 2.4 (1.4, 4.0)]. Mothers in the lowest height tertile had odds of producing a LBW baby [OR 1.8 95% CI (1.2, 2.7)] or a stunted baby [OR 1.6 (1.1, 2.3)]. There is a need to improve the nutritional status of women in KOKAN region which may reduce the risk of NCD.

Weights of Fetal Membranes and Umbilical Cords: Correlation With Placental Pathology

INTRODUCTION

Proper placental gross examination requires weighing the placental disc trimmed of fetal membranes and the umbilical cord. However, untrimmed placental weights are often reported, both in cases submitted for consultation and in publications. Thus, determining the contribution of membranes and cords to untrimmed placental weights would be helpful in estimating the true trimmed weight of placentas. We sought to report the average weights of membranes and cord in term placentas and to correlate these weights with common placental pathologies.

METHODS

A total of 500 consecutive placentas delivered between 36 and 42 weeks gestational age were subjected to a modified grossing protocol, in which the weight of the trimmed and untrimmed placentas, fetal membranes, and umbilical cords were recorded. Acute chorioamnionitis, meconium, maternal vascular malperfusion, and fetal vascular malperfusion were included as pathologic correlates. Clinical data such as the presence of fetal hydrops, intrauterine growth restriction, intrauterine fetal demise, and maternal diabetes were also recorded.

RESULTS

The mean weights of the trimmed placenta, fetal membranes, and umbilical cords were 442 g (180-805 g), 47.2 g (16-108 g), and 37.9 g (9-126 g), respectively. The fetal membranes and umbilical cord weights contributed a mean of 16% to the total untrimmed placental weight. Meconium was associated with heavier fetal membranes. Fetal vascular malperfusion was associated with longer umbilical cord and thus also with heavier umbilical cords. Maternal vascular malperfusion and intrauterine growth restriction were associated with lighter placentas.

DISCUSSION

The trimmed placental disc weight may be estimated by subtracting 16% (ie, weight of the fetal membranes and umbilical cord) from the untrimmed placental weight, or alternatively by subtracting the mean weight of the membranes and umbilical cord. It is important to consider the effects of meconium, fetal and maternal vascular malperfusion, and intrauterine growth restriction on membrane and cord weights when estimating the trimmed placental disc weight.

The impact of umbilical vein blood flow and glucose concentration on blood flow distribution to the fetal liver and systemic organs in healthy pregnancies

Glucose is a major energy substrate for the fetus, including liver, heart, and brain metabolism. The umbilical vein (UV) blood flow supplies the fetal liver directly from the placenta, whereas a fraction is shunted via ductus venosus (DV) to the fetal systemic circulation bypassing the fetal liver. We hypothesized UV glucose concentration to be a major regulator of the distribution of glucose supply between the fetal liver and DV, and explored the influence of maternal metabolic status on this distribution. We included 124 healthy women with normal singleton pregnancies, scheduled for elective cesarean section. UV and DV blood flow measurements were performed by Doppler ultrasound immediately before, and blood samples were obtained during surgery. UV blood flow was significantly correlated with DV blood flow, liver blood flow, and the DV shunting fraction, while UV glucose concentration was not. For normal-weight mothers, the maternal-fetal glucose gradient was positively correlated with DV shunting fraction, and negatively with liver blood flow. For the fetuses of the overweight mothers no such correlation was found. This indicates that within the normal physiological range the human fetus makes adaptations of blood flow to ensure individual needs related to the offered maternal energy supply.

Effect of prenatal nutritional intervention on foetal growth restriction: a real-world study in Shenzhen, China

Objective: Fetal growth restriction (FGR) is the primary cause of infant morbidity and mortality. Although nutritional intervention is generally used to cure FGR, its effects on early- and late-onset FGR have not been reported. This study aimed to resolve this issue in a real-world setting.Study design: We collected the data of pregnant women whose fetuses were diagnosed with FGR and subsequently born at Nanshan Women and Children's Care Hospital in Shenzhen, China. We conducted a MANOVA and series of Cox regression analyses to evaluate the effects of a prenatal nutritional intervention on early and late FGR after adjusting for potential confounders.Results: Our results demonstrated that the average birth weights in the four sub-intervention groups were 50.36-160.05 g higher than those in the nonintervention group. These differences were insignificant with respect to early-onset FGR. In late-onset FGR, however, the interventions led to birth weight increases of 164.95-244.45 g greater than those in the nonintervention group, and these differences were significant. During early-onset FGR, four different nutritional interventions reduced the incidence of small-for-gestational age by 8.00-13.76% relative to the incidence in the nonintervention group, while in late-onset FGR, the incidence decreased by 11.37-17.39%.Conclusions: Our results based on a real-world setting reaffirmed that a prenatal nutritional intervention could improve the birth outcomes in cases of FGR and further suggested a better effectiveness on late-onset FGR.

Changes in maternal blood glucose and lipid concentrations during pregnancy differ by maternal body mass index and are related to birthweight: A prospective, longitudinal study of healthy pregnancies

BACKGROUND

Maternal obesity is increasing worldwide but the consequences for maternal physiology and fetal growth are not fully understood.

OBJECTIVE

To study whether changes in glucose and lipid metabolism during pregnancy differ between women with normal weight and overweight/obesity, and investigate which of these metabolic factors are associated with birthweight.

DESIGN

Prospective, longitudinal study.

SETTING

Department of Obstetrics, Oslo University Hospital, Rikshospitalet.

POPULATION

1031 healthy pregnant women with singleton pregnancies.

METHODS

Blood samples from early and late pregnancy were analyzed for fasting glucose, insulin and lipids (total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides). Associations between metabolic factors and birthweight (z-scores) were explored by linear regression models. Main Outcome Measures: Group-dependent longitudinal changes in glucose and lipids and their association with birthweight (z-scores).

RESULTS

Compared to women with normal weight (BMI < 25), women with overweight (BMI 25-29.9) and obesity (BMI > 30) had significantly higher fasting glucose (4.54, 4.68 and 4.84 mmol/l), insulin (23, 33 and 50 pmol/l), total cholesterol (4.85, 4.99 and 5.14 mmol/l), LDL-C (2.49, 2.66 and 2.88 mmol/l) and triglycerides (1.10, 1.28 and 1.57 mmol/l), but lower HDL-C (1.86, 1.75 and 1.55 mmol/l). BMI (B 0.05, 95% CI 0.03-0.06, p<0.001), gestational weight gain (GWG) (B 0.06, 0.05-0.08, p<0.001) and an increase in fasting glucose (B 0.30, 0.16-0.43, p<0.001) were positively associated with birthweight, whereas a decrease in HDL-C (B -0.72, -0.96- -0.53, p<0.001) had a negative association with birthweight.

CONCLUSIONS

Overweight/obesity was associated with an unfavorable metabolic profile in early pregnancy which was associated with increased birthweight. However, modifiable factors like gestational weight gain and an increase in fasting glucose were identified and can be targeted for interventions.

Association of maternal thyroid function with birthweight: a systematic review and individual-participant data meta-analysis

BACKGROUND

Adequate transplacental passage of maternal thyroid hormone is important for normal fetal growth and development. Maternal overt hypothyroidism and hyperthyroidism are associated with low birthweight, but important knowledge gaps remain regarding the effect of subclinical thyroid function test abnormalities on birthweight-both in general and during the late second and third trimester of pregnancy. The aim of this study was to examine associations of maternal thyroid function with birthweight.

METHODS

In this systematic review and individual-participant data meta-analysis, we searched MEDLINE (Ovid), Embase, Web of Science, the Cochrane Central Register of Controlled Trials, and Google Scholar from inception to Oct 15, 2019, for prospective cohort studies with data on maternal thyroid function during pregnancy and birthweight, and we issued open invitations to identify study authors to join the Consortium on Thyroid and Pregnancy. We excluded participants with multiple pregnancies, in-vitro fertilisation, pre-existing thyroid disease or thyroid medication usage, miscarriages, and stillbirths. The main outcomes assessed were small for gestational age (SGA) neonates, large for gestational age neonates, and newborn birthweight. We analysed individual-participant data using mixed-effects regression models adjusting for maternal age, BMI, ethnicity, smoking, parity, gestational age at blood sampling, fetal sex, and gestational age at birth. The study protocol was pre-registered at the International Prospective Register of Systematic Reviews, CRD42016043496.

FINDINGS

We identified 2526 published reports, from which 36 cohorts met the inclusion criteria. The study authors for 15 of these cohorts agreed to participate, and five more unpublished datasets were added, giving a study population of 48 145 mother-child pairs after exclusions, of whom 1275 (3·1%) had subclinical hypothyroidism (increased thyroid stimulating hormone [TSH] with normal free thyroxine [FT4]) and 929 (2·2%) had isolated hypothyroxinaemia (decreased FT4 with normal TSH). Maternal subclinical hypothyroidism was associated with a higher risk of SGA than was euthyroidism (11·8% vs 10·0%; adjusted risk difference 2·43%, 95% CI 0·43 to 4·81; odds ratio [OR] 1·24, 1·04 to 1·48; p=0·015) and lower mean birthweight (mean difference -38 g, -61 to -15; p=0·0015), with a higher effect estimate for measurement in the third trimester than in the first or second. Isolated hypothyroxinaemia was associated with a lower risk of SGA than was euthyroidism (7·3% vs 10·0%, adjusted risk difference -2·91, -4·49 to -0·88; OR 0·70, 0·55 to 0·91; p=0·0073) and higher mean birthweight (mean difference 45 g, 18 to 73; p=0·0012). Each 1 SD increase in maternal TSH concentration was associated with a 6 g lower birthweight (-10 to -2; p=0·0030), with higher effect estimates in women who were thyroid peroxidase antibody positive than for women who were negative (pinteraction=0·10). Each 1 SD increase in FT4 concentration was associated with a 21 g lower birthweight (-25 to -17; p<0·0001), with a higher effect estimate for measurement in the third trimester than the first or second.

INTERPRETATION

Maternal subclinical hypothyroidism in pregnancy is associated with a higher risk of SGA and lower birthweight, whereas isolated hypothyroxinaemia is associated with lower risk of SGA and higher birthweight. There was an inverse, dose-response association of maternal TSH and FT4 (even within the normal range) with birthweight. These results advance our understanding of the complex relationships between maternal thyroid function and fetal outcomes, and they should prompt careful consideration of potential risks and benefits of levothyroxine therapy during pregnancy.

FUNDING

Netherlands Organization for Scientific Research (grant 401.16.020).

Trans-ethnic meta-analysis of genome-wide association studies identifies maternal ITPR1 as a novel locus influencing fetal growth during sensitive periods in pregnancy

Abnormal fetal growth is a risk factor for infant morbidity and mortality and is associated with cardiometabolic diseases in adults. Genetic influences on fetal growth can vary at different gestation times, but genome-wide association studies have been limited to birthweight. We performed trans-ethnic genome-wide meta-analyses and fine mapping to identify maternal genetic loci associated with fetal weight estimates obtained from ultrasound measures taken during pregnancy. Data included 1,849 pregnant women from four race/ethnic groups recruited through the NICHD Fetal Growth Studies. We identified a novel genome-wide significant association of rs746039 [G] (ITPR1) with reduced fetal weight from 24 to 33 weeks gestation (P<5x10^-8; log₁₀BF>6). Additional tests revealed that the SNP was associated with head circumference (P = 4.85x10^-8), but not with abdominal circumference or humerus/femur lengths. Conditional analysis in an independent sample of mother-offspring pairs replicated the findings and showed that the effect was more likely maternal but not fetal. Trans-ethnic approaches successfully narrowed down the haplotype block that contained the 99% credible set of SNPs associated with head circumference. We further demonstrated that decreased placental expression of ITPR1 was correlated with increased placental epigenetic age acceleration, a risk factor for reduced fetal growth, among male fetuses (r = -0.4, P = 0.01). Finally, genetic risk score composed of known maternal SNPs implicated in birthweight among Europeans was associated with fetal weight from mid-gestation onwards among Whites only. The present study sheds new light on the role of common maternal genetic variants in the inositol receptor signaling pathway on fetal growth from late second trimester to early third trimester.

Clinical Trial Registration: ClinicalTrials.gov, NCT00912132.

Abnormal fetal growth is a risk factor for infant morbidity and mortality, and adult cardiometabolic diseases. Genetic influences on fetal growth can vary at different gestation times. We performed trans-ethnic genome-wide meta-analyses of 1,849 pregnant women from four race/ethnic groups to identify maternal genetic loci associated with ultrasound-based fetal weight estimates at three gestational periods. We identified and validated a novel genome-wide significant association of rs746039 [G] in the ITPR1 gene with reduced fetal weight at end of second trimester. We further demonstrated that decreased placental expression of ITPR1 was correlated with increased placental epigenetic age acceleration, a risk factor for reduced fetal growth, among male fetuses. We evaluated known birthweight loci and identified gestation time-specific associations of six maternal loci with fetal weight. A maternal genetic risk score of birthweight was associated with fetal weight from mid-gestation onwards among Whites. Our study sheds new light on the genetic regulation of gestation time-specific fetal growth.

Elevated Cholesteryl Ester Transfer Protein Activity Early in Pregnancy Predicts Prediabetes 5 Years Later

CONTEXT

Cholesteryl ester transfer protein (CETP) regulates high-density lipoprotein (HDL) cholesterol levels and interaction between glucose, and HDL metabolism is central in the development of diabetes.

OBJECTIVE

We hypothesized that CETP levels would be regulated in diabetic pregnancies. We tested the hypothesis by evaluating CETP activity measured multiple times during pregnancy and at 5 years' follow-up in a prospective cohort (STORK) and investigated its association with gestational diabetes mellitus (GDM) during pregnancy or development of prediabetes 5 years after pregnancy. We also evaluated the strongest correlation of CETP activity among measures of adipocity and glucose metabolism, lipoproteins, adipokines, and monocyte/macrophage activation markers.

DESIGN

A population-based longitudinal cohort study was conducted from 2001 to 2013.

SETTING

The study setting was Oslo University Hospital.

PATIENTS OR OTHER PARTICIPANTS

A total of 300 women during pregnancy and at 5 years postpartum participated in this study.

MAIN OUTCOME MEASURES

CETP activity was measured at 14 to 16, 22 to 24, 30 to 32, and 36 to 38 weeks' gestation, and at 5 years' follow-up.

RESULTS

We found higher CETP activity in pregnancy in women developing prediabetes but no association with GDM. CETP activity decreased throughout pregnancy and remained low at follow-up. High CETP activity was associated with sCD14 levels, in particular in women who developed prediabetes. These data show that enhanced CETP activity during pregnancy is associated with systemic indices of monocyte/macrophage activation, in particular in women who develop prediabetes later in life.

CONCLUSIONS

CETP activity during pregnancy identifies women at risk for later diabetes development.

Influence of maternal and placental factors on newborn body composition

AIM

The objective of this study was to assess whether maternal characteristics, placental size or histological chorioamnionitis was associated with newborn body composition. Furthermore, we sought to determine whether placental weight may mediate the association between maternal pre-pregnancy weight and age with newborn body composition.

METHODS

A cross-sectional study was conducted at Royal Prince Alfred Hospital, Sydney, Australia. This study included 136 healthy, singleton, term-born newborns. Recruitment was stratified by newborn body fat percentiles (gender and gestational adjusted). Body fat was assessed by air displacement plethysmography. Placental examination was conducted by an anatomical pathologist. Maternal (chorioamnionitis) and fetal (chorionic and umbilical vasculitis, funisitis) inflammatory responses were classified according to Redline criteria.

RESULTS

Maternal pre-pregnancy weight, parity, labour, placental weight and surface area were associated with newborn fat mass and fat-free mass. Gestational diabetes and maternal age were associated with newborn fat mass but not fat-free mass. There was no association between histological chorioamnionitis and newborn body composition; however, spontaneous onset of labour was strongly associated with the presence of histological chorioamnionitis. Only 25-31% of the association of maternal weight and age with newborn fat mass was mediated via the placenta.

CONCLUSIONS

Maternal factors associated with newborn fat mass and fat-free mass differed, indicating that different mechanisms control fat mass and fat-free mass. Our mediation analysis suggests that placental weight partly mediates the association of maternal factors with newborn body composition. Histological chorioamnionitis was not associated with newborn body composition.