Placental programming of chronic diseases, cancer and lifespan: A review

Tebuconazole exposure disrupts placental function and causes fetal low birth weight in rats

Tebuconazole (TEB) is one of the widely used broad-spectrum triazole fungicides. Its accumulation in mammals leads to various endocrine disruptions. However, it is unclear whether the exposure of TEB during pregnancy affects the growth and development of fetus and placenta. Here, TEB was exposed to pregnant Sprague-Dawley female rats from gestational days 12-21 of 0, 25, 50 or 100 mg/kg for 10 days. TEB reduced placental estradiol levels. TEB disrupted the structure and function of the placenta, leading to hypertrophy, fibrin exudation, edema, calcification, arterial fibroblast proliferation, and trophoblastic infarction. RNA-seq analysis showed that TEB mainly down-regulated the expression of iron transport genes and up-regulated the expression of genes for immune/inflammatory responses. Further qPCR showed that TEB down-regulated Tfrc, Hamp, Eif2ak2 and up-regulated the expression of Cd34, Cd36, Jag1, Pln, Cyp1a1, Esrra, and Aqp1 at 50 and 100 mg/kg. Western blot and semi-quantitative immunohistochemical staining also demonstrated that TEB lowered the levels of TFRC and EIF2AK2 and increased the levels of CD34, CD36, JAG1, CYP1A1, and ESRRA at 50 and 100 mg/kg. In conclusion, TEB severely damages the structure and function of the placenta, leading to hypertrophy of the placenta, low birth weight and feminization of the male fetus possibly via several pathways including iron transport and TNF signaling.

Spiral Arteries in Second Trimester of Pregnancy: When Is It Possible to Define Expected Physiological Remodeling as Abnormal?

After undergoing remodeling, uterine spiral arteries turn into wide, flexible tubes, with low resistance. If remodeling does not occur, spontaneous abortions, intrauterine growth restriction, and pregnancy-related hypertensive disorders can ensue. Arterial transformation begins at a very early gestational stage; however, second quarter pregnancy histopathological samples have yet to pinpoint the exact moment when abnormal remodeling transpires. We examined 100 samples, taken from consecutive abortions at 12-23 gestational weeks. Following Pijnenborg and Smith guidelines, blinded pathologists analyzed clinical data on remodeling stages. Lab results showed that arterial remodeling is not synchronic in all vessels; a single sample can include various remodeling stages; neither is remodeling homogenous in a single vessel: change may be occurring in one part of the vessel, but not in another. To our knowledge, no one has published this finding. In the examined age group, Smith stage IV predominates; around week 14, substantial muscle and endothelium loss takes place. After week 17, endovascular or fibrin trophoblast does not usually occur. Although scant consensus exists on what defines preeclampsia etiology, it is clear that it involves abnormal remodeling in decidua vessels. Improved understanding requires further knowledge on both the physiological and pathological aspects of the remodeling process. We observed that muscle and endothelial tissues disappear from weeks 14-17, after which time reendothelization predominates. We list the expected proportion of spiral artery changes for each gestational age which, to date, has not been available.

Sexual dimorphism and the placenta - results from the ROLO kids study

BACKGROUND/AIMS

To assess the association between placental morphology and neonatal and infant anthropometry, including analysis by sex.

STUDY DESIGN

Data from the ROLO Kids [Randomized COntrol Trial of LOw Glycaemic Index in Pregnancy] study were analyzed including placental weight and morphology. Placental, anthropometric and skinfold measurements were recorded as markers of adiposity in 196 neonates and 215 infants at 6 months of age. Ratios including subscapular-to-triceps skinfold ratio and waist-to-height ratio were used as markers of central adiposity, while the sum of all skinfolds and subscapular plus triceps skinfolds were used as markers of general adiposity. Analysis was performed for total groups and by sex.

RESULTS

On simple linear regression placental weight was associated with neonatal and infant anthropometric measurements. On multiple regression, the placental weight was associated with birth weight. In the neonatal period placental weight was associated with general adiposity in males only (sum of skinfolds (B 0.007, p < .001) and subscapular + triceps skinfolds a marker of general adiposity (B 0.004 p < .001)). At 6 months of age placental length was positively associated with central adiposity in the total group (B 0.006, p .036) and maximum cord diameter was inversely associated with infant central adiposity (B - 0.309 p .043) in males only.

CONCLUSION

The placental phenotype is associated with anthropometry at birth and this association persists to early infancy with a stronger relationship noted in this cohort amongst males. This suggests sexual dimorphism may play a role in the impact of the placenta on infant anthropometry.

Social Determinants of Placental Health and Future Disease Risks for Babies

Birthweight is a well-known predictor of adult-onset chronic disease. The placenta plays a necessary role in regulating fetal growth and determining birth size. Maternal stressors that affect placental function and prenatal growth include maternal overnutrition and undernutrition, toxic social stress, and exposure to toxic chemicals. These stressors lead to increased vulnerability to disease within any population. This vulnerability arises from placental and fetal exposure to stressors during fetal life. The biological drivers linking various social determinants of health to compromised placental function and fetal development have been little studied.

The physiological effect of early pregnancy on a woman's response to a submaximal cardiopulmonary exercise test

Given all its systemic adaptive requirements, pregnancy shares several features with physical exercise. In this pilot study, we aimed to assess the physiological response to submaximal cardiopulmonary exercise testing (CPET) in early pregnancy. In 20 healthy, pregnant women (<13 weeks gestation) and 20 healthy, non-pregnant women, we performed a CPET with stationary cycling during a RAMP protocol until 70% of the estimated maximum heart rate (HR) of each participant. Hemodynamic and respiratory parameters were non-invasively monitored by impedance cardiography (PhysioFlow® ) and a breath-by-breath analyzer (OxyconTM ). To compare both groups, we used linear regression analysis, adjusted for age. We observed a similar response of stroke volume, cardiac output (CO) and HR to stationary cycling in pregnant and non-pregnant women, but a slightly lower 1-min recovery rate of CO (-3.9 [-5.5;-2.3] vs. -6.6 [-8.2;-5.1] L min-1  min-1 ; p = .058) and HR (-38 [-47; -28] vs. -53 [-62; -44] bpm/min; p = .065) in pregnant women. We also observed a larger increase in ventilation before the ventilatory threshold (+6.2 [5.4; 7.0] vs. +3.2 [2.4; 3.9] L min-1  min-1 ; p < .001), lower PET CO2 values at the ventilatory threshold (33 [31; 34] vs. 36 [34; 38] mmHg; p = .042) and a larger increase of breathing frequency after the ventilatory threshold (+4.6 [2.8; 6.4] vs. +0.6 [-1.1; 2.3] breaths min-1  min-1 ; p = .015) in pregnant women. In conclusion, we observed a slower hemodynamic recovery and an increased ventilatory response to exercise in early pregnancy.

Reduced hepatic metallothionein expression in first trimester fetuses in response to intrauterine smoking exposure: a consequence of low maternal zinc levels?

STUDY QUESTION

Does maternal smoking in early pregnancy affect metallothionein 1 and 2 (MT1 and MT2) mRNA and protein expression in first trimester placenta or embryonic/fetal liver?

SUMMARY ANSWER

In the first trimester, MT protein expression is seen only in liver, where smoking is associated with a significantly reduced expression.

WHAT IS KNOWN ALREADY

Zinc homeostasis is altered by smoking. Smoking induces MT in the blood of smokers properly as a result of the cadmium binding capacities of MT. In term placenta MT is present and smoking induces gene and protein expression (MT2 in particular), but the MT presence and response to smoking have never been examined in first trimester placenta or embryonic/fetal tissues.

STUDY DESIGN, SIZE, DURATION

Cross sectional study where the presence of MT mRNA and protein was examined at the time of the abortion. The material was collected with informed consent after surgical intervention and frozen immediately. For protein expression analysis, liver tissue originating from smoking exposed n = 10 and unexposed n = 12 pregnancies was used. For mRNA expression analyses, placental tissue originating from smokers n = 19 and non-smokers n = 23 and fetal liver tissue from smoking exposed n = 16 and smoking unexposed pregnancies n = 13, respectively, were used.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Tissues were obtained from women who voluntarily and legally chose to terminate their pregnancy between gestational week 6 and 12. Western blot was used to determine the protein expression of MT, and real-time PCR was used to quantify the mRNA expression of MT2A and eight MT1 genes alongside the expression of key placental zinc transporters: zinc transporter protein-1 (ZNT1), Zrt-, Irt-related protein-8 and -14 (ZIP8 and ZIP14).

MAIN RESULTS AND THE ROLE OF CHANCE

A significant reduction in the protein expression of MT1/2 in liver tissue (P = 0.023) was found by western blot using antibodies detecting both MT forms. Overall, a similar tendency was observed on the mRNA level although not statistically significant. Protein expression was not present in placenta, but the mRNA regulation suggested a down regulation of MT as well. A suggested mechanism based on the known role of MT in zinc homeostasis could be that the findings reflect reduced levels of easily accessible zinc in the blood of pregnant smokers and hence a reduced MT response in smoking exposed fetal/embryonic tissues.

LIMITATIONS AND REASONS FOR CAUTION

Smoking was based on self-reports; however, our previous studies have shown high consistency regarding cotinine residues and smoking status. Passive smoking could interfere but was found mainly among smokers. The number of fetuses was limited, and other factors such as medication and alcohol might affect the findings. Information on alcohol was not consistently obtained, and we cannot exclude that it was more readily obtained from non-users. In the study, alcohol consumption was reported by a limited number (less than 1 out of 5) of women but with more smokers consuming alcohol. However, the alcohol consumption reported was typically limited to one or few times low doses. The interaction between alcohol and smoking is discussed in the paper. Notably we would have liked to measure zinc status to test our hypothesis, but maternal blood samples were not available.

WIDER IMPLICATIONS OF THE FINDINGS

Zinc deficiency-in particular severe zinc deficiency-can affect pregnancy outcome and growth. Our findings indicate that zinc homeostasis is also affected in early pregnancy of smokers, and we know from pilot studies that even among women who want to keep their babies, the zinc status is low. Our findings support that zinc supplements should be considered in particular to women who smoke.

STUDY FUNDING/COMPETING INTEREST(S)

We thank the Department of Biomedicine for providing laboratory facilities and laboratory technicians and the Lundbeck Foundation and Læge Sofus Carl Emil Friis og Hustru Olga Doris Friis Legat for financial support. The authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

N/A.

Mid-gestational fetal placental blood flow is diminished in the fetus with congenital heart disease

OBJECTIVE

Data suggest fetuses with congenital heart disease (CHD) have placental abnormalities. Their abnormal placental vasculature may affect fetal placental blood flow, which has not previously been explored.

METHOD

We performed a retrospective cross-sectional study comparing umbilical venous volume flow (UVVF) of single ventricle, D-transposition of the great arteries, and tetralogy of Fallot fetuses with fetuses without CHD. UVVF and combined cardiac output (CCO) were calculated from fetal echocardiography and compared using t tests, χ² and Fisher's exact tests.

RESULTS

Mean gestational age and fetal weight were greater in CHD fetuses (26.5 weeks, 1119.4 g; n = 81, P < .001) compared to controls (23.1 weeks, 675 g; n = 170, P < .001). UVVF/fetal weight was nevertheless decreased among cases (99.8 vs 115.3 mL/min/kg, P < .001). Subgroup analysis of 20- to 25-week fetuses demonstrated no significant differences in case and control baseline characteristics. In CHD fetuses (n = 31) compared to controls (n = 144), absolute UVVF (50.8 vs 62.1 mL/min, P = .006), and UVVF/fetal weight (98.8 vs 118.5 mL/min/kg, P < .001) were decreased. Findings were similar in single ventricle (n = 24) and hypoplastic left heart syndrome (n = 14).

CONCLUSION

Mid-gestational placental blood flow in CHD fetuses is decreased compared to controls. Further study is needed to explore the relationship between UVVF and placental pathology, and impact on outcomes.

Determinants of placental leptin receptor gene expression and association with measures at birth

INTRODUCTION

The leptin signalling pathway is important in metabolic health during pregnancy. However, few studies have investigated the determinants and extent of leptin receptor gene (LEPR) expression in the placenta, nor the relationship with infant health in early life. Here, we investigate the genetic and maternal in utero determinants of placental LEPR expression, and whether this expression is linked to anthropometric and inflammatory measures at birth in healthy newborns in the Barwon Infant Study.

METHODS

Placental LEPR expression was measured using RT-qPCR (n = 854 placentae). Associations between genetic variation in LEPR, maternal in utero factors, measures at birth and placental LEPR expression were assessed using multivariable linear regression modelling.

RESULTS

We found that the genotype at two intronic SNPs, rs9436301 and rs9436746, was independently associated with placental LEPR expression. Maternal pre-pregnancy body mass index, gestational diabetes mellitus, weight gain and smoking in pregnancy were not associated with LEPR expression. Placental LEPR expression was negatively associated with high sensitivity C-Reactive Protein in umbilical cord blood, which persisted after adjustment for potential confounders.

DISCUSSION

Overall, our findings suggest that genetic variation in LEPR plays a key role in regulating placental LEPR expression, which is in turn is associated with inflammatory markers in cord blood at birth. Further studies encompassing other aspects of leptin signalling are warranted to understand if these relationships are causal and have health implications.

An interaction between fetal sex and placental weight and efficiency predicts intrauterine growth in response to maternal protein insufficiency and gestational exposure window in a mouse model of FASD

BACKGROUND

Individuals exposed to gestational stressors such as alcohol exhibit a spectrum of growth patterns, suggesting individualized responses to the stressors. We hypothesized that intrauterine growth responses to gestational alcohol are modified not only by the stressor's severity but by fetal sex and the placenta's adaptive capacity.

METHODS

Pregnant C57BL/6J mice were assigned to one of three groups. Group 1 consumed a normal protein diet (18% protein by weight) and received 4.5 g alcohol/kg body weight (NP-Alc-8) or isocaloric maltodextrin (NP-MD-8) daily from embryonic day (E) 8.5-E17.5. Group 2 consumed the same diet but received alcohol (NP-Alc-13) or maltodextrin (NP-MD-13) daily from E13.5-E17.5. Group 3 consumed the same diet but containing a lower protein content (12% protein by weight) from E0.5 and also received alcohol (LP-Alc-8) or maltodextrin (LP-MD-8) daily from E8.5-E17.5. Maternal, placental, and fetal outcomes were assessed on E17.5 using 2-way ANOVA or mixed linear model.

RESULTS

We found that intrauterine growth differed in the alcohol-exposed fetuses depending on sex and insult severity. Both NP-Alc-8 (vs. NP-MD-8) males and females had lower body weight and asymmetrical growth, but only NP-Alc-8 females had lower placental weight (P < 0.05). NP-Alc-13 (vs. NP-MD-13) females, but not their male littermates, had lower body weight (P = 0.019). Alcohol exposure beginning from E8.5 (vs. E13.5) decreased the ratio of fetal liver-to-body weight and increased the ratio of fetal brain-to-liver weight in both sexes (P < 0.05). LP-Alc-8 (vs. NP-MD-8) group had smaller litter size (P = 0.048), but the survivors had normal placental and body weight at E17.5. Nevertheless, LP-Alc-8 fetuses still showed asymmetrical growth. Correlation analyses reveal a relationship between litter size and placental outcomes, which were related to fetal outcomes in a sex-dependent manner, suggesting that the placenta may mediate the consequence of LP-Alc-altered litter size on fetal development.

CONCLUSIONS

Our data indicate that the placenta is strongly involved in the fetal stress response and adapts in a sex-dependent fashion to support fetal development under the alcohol stressor. These variables may further influence the spectrum of intrauterine growth outcomes observed in those diagnosed with fetal alcohol spectrum disorder.

Placental function in maternal obesity

Maternal obesity is associated with pregnancy complications and increases the risk for the infant to develop obesity, diabetes and cardiovascular disease later in life. However, the mechanisms linking the maternal obesogenic environment to adverse short- and long-term outcomes remain poorly understood. As compared with pregnant women with normal BMI, women entering pregnancy obese have more pronounced insulin resistance, higher circulating plasma insulin, leptin, IGF-1, lipids and possibly proinflammatory cytokines and lower plasma adiponectin. Importantly, the changes in maternal levels of nutrients, growth factors and hormones in maternal obesity modulate placental function. For example, high insulin, leptin, IGF-1 and low adiponectin in obese pregnant women activate mTOR signaling in the placenta, promoting protein synthesis, mitochondrial function and nutrient transport. These changes are believed to increase fetal nutrient supply and contribute to fetal overgrowth and/or adiposity in offspring, which increases the risk to develop disease later in life. However, the majority of obese women give birth to normal weight infants and these pregnancies are also associated with activation of inflammatory signaling pathways, oxidative stress, decreased oxidative phosphorylation and lipid accumulation in the placenta. Recent bioinformatics approaches have expanded our understanding of how maternal obesity affects the placenta; however, the link between changes in placental function and adverse outcomes in obese women giving birth to normal sized infants is unclear. Interventions that specifically target placental function, such as activation of placental adiponectin receptors, may prevent the transmission of metabolic disease from obese women to the next generation.

Maternal dietary deficiency of n-3 fatty acids affects metabolic and epigenetic phenotypes of the developing fetus

Polyunsaturated fatty acids (PUFAs) play multiple physiological roles. They regulate the structure and function of cell membranes and cell growth and proliferation, and apoptosis. In addition, PUFAs are involved in cellular signaling, gene expression and serve as precursors to second messengers such as eicosanoids, docosanoids etc. and regulate several physiological processes including placentation, inflammation, immunity, angiogenesis, platelet function, synaptic plasticity, neurogenesis, bone formation, energy homeostasis, pain sensitivity, stress, and cognitive functions. Linoleic acid, 18:2n-6 (LA) and alpha-linolenic acid, 18:3n-3 (ALA) are the two essential fatty acids obtained from the diets and subsequently their long-chain polyunsaturated fatty acids (LCPUFAs) are accumulated in the body. The maternal plasma LCPUFAs especially accumulated in larger amounts in the brain during the third trimester of pregnancy via the placenta and postnatally from mother's breast milk. Various studies, including ours, suggest PUFA's important role in placentation, as well as in growth and development of the offspring. However, intakes of maternal n-3 PUFAs during pregnancy and lactation are much lower in India compared with the Western population. In India, n-3 fatty acid status is further reduced by higher intake of n-6 PUFA rich oils and trans fats. More data on the impacts of long term maternal n-3 PUFA deficiency on placental structure and function, gene expression, epigenetic changes and resultant cognitive function of fetus & infants are emerging. This review summarizes the impacts of n-3 PUFA deficiency in utero on fetal growth and development, adiposity, energy metabolism, musculoskeletal development, and epigenetic changes in feto-placental axis from the recently available pre-clinical and clinical data.

Automated Placenta Segmentation with a Convolutional Neural Network Weighted by Acoustic Shadow Detection

Placental assessment through routine obstetrical ultrasound is often limited to documenting its location and ruling out placenta previa. However, many obstetrical complications originate from abnormal focal or global placental development. Technical difficulties in assessing the placenta as well as a lack of established objective criteria to classify echotexture are barriers to diagnosis of pathology by ultrasound imaging. As a first step towards the development of a computer aided placental assessment tool, we developed a fully automated method for placental segmentation using a convolutional neural network. The network contains a novel layer weighted by automated acoustic shadow detection to recognize artifacts specific to ultrasound. In order to develop a detection algorithm usable in different imaging scenarios, we acquired a dataset containing 1364 fetal ultrasound images from 247 patients acquired over 47 months was taken with different machines, operators, and at a range of gestational ages. Mean Dice coefficients for automated segmentation on the full dataset with and without the acoustic shadow detection layer were 0.92±0.04 and 0.91±0.03 when comparing to manual segmentation. Mean Dice coefficients on the subset of images containing acoustic shadows with and without acoustic shadow detection were 0.87±0.04 and 0.75±0.05. The method requires no user input to tune the detection. The automated placenta segmentation method can serve as a preprocessing step for further image analysis in artificial intelligence methods requiring large scale data processing of placental images.

Relationships between metabolic markers and obesity measures in two populations that differ in stature-The SAMINOR Study

Background

The relationships between metabolic markers and obesity measures may differ by ethnicity, sex, and height. Questions have been posed whether these relationships differ by ethnicity in the population in Northern Norway, but this has not been explored yet.

Objectives

Investigate the relationships between metabolic markers and obesity measures in Sami and non‐Sami and explore the impact of stature.

Methods

In total, 13 921 men and women aged 30 and 36 to 79 years (22.0% Sami) from a population‐based cross‐sectional survey in Norway, the SAMINOR 1 Survey (2003‐2004, 57.2% attendance), were included. Relationships between triglycerides, high‐density lipoprotein cholesterol, glucose, systolic/diastolic blood pressure (BP), metabolic syndrome and diabetes mellitus as outcomes, and body mass index (BMI), waist circumference (WC), and waist‐to‐height ratio (WHtR), respectively, were modelled using fractional polynomial regression. Appropriate interaction analyses and adjustments were made.

Results

The non‐Sami were approximately 6 cm taller than the Sami. No interactions were found between ethnicity and obesity. At the same levels of WC, BMI, or WHtR, levels of lipids and BP differed marginally between Sami and non‐Sami, but these were eliminated by height adjustment, with one exception: At any given WC, BMI, or WHtR, Sami had approximately 1.4 mmHg (95% CI, −2.1 to −0.7) lower systolic BP than non‐Sami (P values < .001).

Conclusions

Height explained the marginal ethnic differences in metabolic markers at the same level of obesity, except for systolic BP, which was lower in Sami than in non‐Sami at any given BMI, WC, or WHtR.

Reactive oxygen species-mediated cellular genotoxic stress is involved in 1-nitropyrene-induced trophoblast cycle arrest and fetal growth restriction

1-nitropyrene (1-NP) is a key component of diesel exhaust-sourced fine particulate matter (PM2.5). Our recent study demonstrated that gestational 1-NP exposure caused placental proliferation inhibition and fetal intrauterine growth restriction (IUGR). This study aimed to investigate the role of genotoxic stress on 1-NP-induced placental proliferation inhibition and fetal IUGR. Human trophoblasts were exposed to 1-NP (10 μM). Growth index was reduced and PCNA was downregulated in 1-NP-exposed placental trophoblasts. More than 90% of 1-NP-exposed trophoblasts were arrested in either G0/G1 or G2/M phases. CDK1 and cyclin B, two G2/M cycle-related proteins, and CDK2, a G0/G1 cycle-related protein, were reduced in 1-NP-exposed trophoblasts. Phosphorylated Rb, a downstream molecule of CDK2, was inhibited in 1-NP-exposed trophoblasts. Moreover, DNA double-strand break was observed and γ-H2AX, another indicator of DNA double-strand break, was upregulated in 1-NP-exposed trophoblasts. Phosphorylated ATM, a key molecule of genotoxic stress, and its downstream molecule Chk2 were elevated. By contrast, Cdc25A, a downstream target of Chk2, was reduced in 1-NP-exposed trophoblasts. Phenyl-N-t-butylnitrone (PBN), a free radical scavenger, inhibited 1-NP-induced genotoxic stress and trophoblast cycle arrest. Animal experiment showed that N-acetylcysteine (NAC), an antioxidant, rescued 1-NP-induced placental proliferation inhibition and fetal IUGR in mice. These results provide evidence that reactive oxygen species (ROS)-mediated cellular genotoxic stress partially contributes to 1-NP-induced placental proliferation inhibition and fetal IUGR.

Appraising causal relationships of dietary, nutritional and physical-activity exposures with overall and aggressive prostate cancer: two-sample Mendelian-randomization study based on 79 148 prostate-cancer cases and 61 106 controls

BACKGROUND

Prostate cancer is the second most common male cancer worldwide, but there is substantial geographical variation, suggesting a potential role for modifiable risk factors in prostate carcinogenesis.

METHODS

We identified previously reported prostate cancer risk factors from the World Cancer Research Fund (WCRF)'s systematic appraisal of the global evidence (2018). We assessed whether each identified risk factor was causally associated with risk of overall (79 148 cases and 61 106 controls) or aggressive (15 167 cases and 58 308 controls) prostate cancer using Mendelian randomization (MR) based on genome-wide association-study summary statistics from the PRACTICAL and GAME-ON/ELLIPSE consortia. We assessed evidence for replication in UK Biobank (7844 prostate-cancer cases and 204 001 controls).

RESULTS

WCRF identified 57 potential risk factors, of which 22 could be instrumented for MR analyses using single nucleotide polymorphisms. For overall prostate cancer, we identified evidence compatible with causality for the following risk factors (odds ratio [OR] per standard deviation increase; 95% confidence interval): accelerometer-measured physical activity, OR = 0.49 (0.33-0.72; P = 0.0003); serum iron, OR = 0.92 (0.86-0.98; P = 0.007); body mass index (BMI), OR = 0.90 (0.84-0.97; P = 0.003); and monounsaturated fat, OR = 1.11 (1.02-1.20; P = 0.02). Findings in our replication analyses in UK Biobank were compatible with our main analyses (albeit with wide confidence intervals). In MR analysis, height was positively associated with aggressive-prostate-cancer risk: OR = 1.07 (1.01-1.15; P = 0.03).

CONCLUSIONS

The results for physical activity, serum iron, BMI, monounsaturated fat and height are compatible with causality for prostate cancer. The results suggest that interventions aimed at increasing physical activity may reduce prostate-cancer risk, although interventions to change other risk factors may have negative consequences on other diseases.

Maternal 25-Hydroxyvitamin D Deficiency Promoted Metabolic Syndrome and Downregulated Nrf2/CBR1 Pathway in Offspring

Metabolic syndrome is a disorder of energy use and storage, which is characterized by central obesity, dyslipidemia, and raised blood pressure and blood sugar levels. Maternal 25-hydroxyvitamin D deficiency is known to cause metabolic changes, chronic disease, and increased adiposity in adulthood. However, the underlying mechanism of induced metabolic syndrome (MetS) in the offspring in vitamin D deficient pregnant mothers remains unclear. We identified that maternal 25-hydroxyvitamin D deficiency enhances oxidative stress, which leads to the development of MetS in the mother and her offspring. Further, immunohistochemical, Western blotting, and qRT-PCR analyses revealed that maternal 25-hydroxyvitamin D deficiency inhibited the activation of the Nrf2/carbonyl reductase 1 (CBR1) pathway in maternal placenta, liver, and pancreas, as well as the offspring's liver and pancreas. Further analyses uncovered that application of 25-hydroxyvitamin D activated the Nrf2/CBR1 pathway, relieving the oxidative stress in BRL cells, suggesting that 25-hydroxyvitamin D regulates oxidative stress in offspring and induces the activation of the Nrf2/CBR1 pathway. Taken together, our study finds that maternal 25-hydroxyvitamin D deficiency is likely to result in offspring's MetS probably via abnormal nutrition transformation across placenta. Depression of the Nrf2/CBR1 pathway in both mothers and their offspring is one of the causes of oxidative stress leading to MetS. This study suggests that 25-hydroxyvitamin D treatment may relieve the offspring's MetS.

The fetal/placental weight ratio is associated with the incidence of atopic dermatitis in female infants during the first 14 months: The Hamamatsu Birth Cohort for Mothers and Children (HBC Study)

Background

Among atopic diseases, atopic dermatitis is the most common allergic disease in children and influences both infantile and parental quality of life.

Objective

The present study investigated the sex-specific relationship between the fetal/placental weight ratio and The incidence of atopic dermatitis in infants during the first 14 months of life.

Methods

Study participants were 922 infants (462 female and 460 male) from singleton pregnancies enrolled in the Hamamatsu Birth Cohort for Mothers and Children (HBC Study) after the exclusion of 298 with missing data on atopic dermatitis. The enrollment of infants with atopic dermatitis was based on a positive response from parents regarding whether a physician had ever diagnosed their child with atopic dermatitis by 14 months of age. The two-sample Wilcoxon rank-sum test or χ² test was adopted for descriptive analyses where appropriate. Unadjusted odds ratios and 95% confidence intervals for the infantile incidence of atopic dermatitis were compared using logistic regression analyses.

Results

Maternal and perinatal factors did not correlate with the incidence of infantile atopic dermatitis. Fetal/placental weight ratio, but not birth or placental weight, correlated with the incidence of atopic dermatitis in female, but not male, infants. A correlation was still observed after adjustments for maternal allergies, gestational age at birth, maternal smoking during pregnancy, and household income at birth (odds ratio: 1.57; 95% confidence interval, 1.05-2.33).

Conclusion

We speculated that the intrauterine fetal environment, represented by a relatively small placenta, programs a predisposition in only female infants to atopic dermatitis during the first 14 months of life.

Metabolomic identification of placental alterations in fetal growth restriction

Introduction: Fetal growth restriction (FGR), viz., birth weight <10th percentile is a common pregnancy complication which increases the risk of adverse fetal and newborn outcomes. The placenta is the key organ for fetal growth as it controls oxygen and nutrient availability. This study aims to elucidate the mechanisms of and identify putative placental biomarkers for FGR using high-resolution metabolomics.Methods: Placenta samples from 19 FGR cases and 30 controls were analyzed using proton magnetic resonance (¹H NMR) spectroscopy and direct flow injection mass spectrometry with reverse-phase liquid-chromatography mass spectrometry (DI-LC-MS/MS). Significant concentration differences (p-value <.05) in 179 of the 220 metabolites were measured.Results: Of the 179 metabolites, 176 (98.3%) had reduced placental levels in FGR cases. The best performing metabolite model: 3-hydroxybutyrate, glycine and PCaaC42:0 achieved an AUC (95% CI) = 0.912 (0.814-1.000) with a sensitivity of 86.7% and specificity of 84.2% for FGR detection. Metabolite set enrichment analysis (MSEA) revealed significant (p < .05) perturbation of multiple placental metabolite pathways including urea metabolism, ammonia recycling, porphyrin metabolism, bile acid biosynthesis, galactose metabolism and perturbed protein biosynthesis.Conclusion: The placental metabolic pathway analysis revealed abnormalities that are consistent with fetal hepatic dysfunction in FGR. Near global reduction of metabolite concentrations was found in the placenta from FGR cases and metabolites demonstrated excellent diagnostic accuracy for FGR detection.

Normally Grown Non-dysmorphic Stillbirth Post 38 Weeks Gestation and Reduced Fetal Movements: A Matter of Reserve? A Retrospective Study

This study investigates the relationship between placental weight relative to birthweight and risk of stillbirth in non-dysmorphic fetuses ≥ 38 weeks gestation with no evidence of intrauterine growth restriction. This is a retrospective study of stillbirths who underwent post-mortem between 1st Jan 2011 and 31st Dec 2018 in South East Scotland (n = 55). The control group (n = 74) was matched for gestation, age of mother and maternal BMI. There was a significant difference (p = 0.0117) in the mean ratio of birth weight to placental weight (BW:PW) between the stillbirth group (8.17) and control group (7.33). Cases of stillbirths where the mother had reported reduced fetal movements (RFM) had a higher BW:PW compared to controls (p = 0.024). Within the RFM stillbirth group, 5/6 (83%) cases showed significant changes of maternal vascular malperfusion (MVM) and/or fetal vascular malperfusion (FVM); whilst within the RFM control group, 5/15 (33%) cases showed significant changes of MVM and/or FVM. There is a significantly higher BW:PW within the stillbirth group than within the control group, both groups show changes of MVM and/or FVM and our supposition is that these changes have a greater impact on placental reserve when the birthweight is high relative to placental weight. Reduced fetal movements may indicate diminished placental reserve. We propose that the ability to predict a high BW:PW within pregnancies where the mothers report RFM may help to prevent late stillbirth in non-IUGR infants.

Complex, coordinated and highly regulated changes in placental signaling and nutrient transport capacity in IUGR

The most common cause of intrauterine growth restriction (IUGR) in the developed world is placental insufficiency, a concept often used synonymously with reduced utero-placental and umbilical blood flows. However, placental insufficiency and IUGR are associated with complex, coordinated and highly regulated changes in placental signaling and nutrient transport including inhibition of insulin and mTOR signaling and down-regulation of specific amino acid transporters, Na+/K+-ATPase, the Na+/H+-exchanger, folate and lactate transporters. In contrast, placental glucose transport capacity is unaltered and Ca2+-ATPase activity and the expression of proteins involved in placental lipid transport are increased in IUGR. These findings are not entirely consistent with the traditional view that the placenta is dysfunctional in IUGR, but rather suggest that the placenta adapts to reduce fetal growth in response to an inability of the mother to allocate resources to the fetus. This new model has implications for the understanding of the mechanisms underpinning IUGR and for the development of intervention strategies.

Maternal Tobacco Smoke Exposure Causes Sex-Divergent Changes in Placental Lipid Metabolism in the Rat

Maternal tobacco smoke exposure (MTS) affects fetal acquisition of long-chain polyunsaturated fatty acids (LCPUFA) and increases the risk of obesity and cardio-metabolic disease in the offspring. Alterations in fetal LCPUFA acquisition in maternal smoking are mediated by the placenta. The handling of LCPUFA by the placenta involves protein-mediated transfer and storage. Molecular mediators of placental LCPUFA handling include PPARγ and the fatty acid transport proteins. We previously demonstrated, in a rat model, that MTS results in programming of adult-onset obesity and metabolic disease in male, but not female, offspring. In this study, we test the hypothesis that in utero MTS exposure alters placental structure, placental LCPUFA handling, and fetal fatty acid levels, in a sex-divergent manner. We exposed pregnant rats to tobacco smoke from embryonic day 11 to term gestation. We measured placental and fetal fatty acid profiles, the systolic/diastolic ratio (SD ratio), placental histology, and expression of molecular mediators in the placenta. Our primary finding is that MTS alters fatty acid profiles in male, but not female fetuses and placenta, including increasing the ratio of omega-6 to omega-3 fatty acids. MTS also increased SD ratio in male, but not female placenta. In contrast, the expression of PPARγ and FATPs was upregulated in female, but not male placenta. We conclude that MTS causes sex-divergent changes in placental handling of LCPUFA in the rat. We speculate that our results demonstrate an adaptive response to MTS by the female placenta.

Placental weights from normal deliveries in Ireland

BACKGROUND

The weight of the delivered placenta gives a useful representation of placental function in utero. In the absence of Irish data, many pathologists rely on data from other populations, many of which are now 15 to 30 years old. The development of a population-specific nomogram would aid in the examination of placentas after delivery, allowing pathologists and medical scientists to more easily distinguish between placental physiological changes and pathology.

AIMS

To record placental weights among women having a singleton delivery in Dublin and to establish median placental weights for each gestational age after 37 weeks.

METHODS

Prospective cohort study in a Tertiary level University Hospital. All singleton pregnancies were included; stillbirths, multiple gestations, and cases with obstetric complications involving the placenta were excluded. The placentas were weighed both untrimmed and trimmed with standard scales. Demographic features including birth weight and maternal parity were also recorded.

RESULTS

Four hundred thirty placentas were weighed over a 6-week period. A median term placental weight based on gestational age was established, with a range from the tenth to ninetieth centiles.

CONCLUSION

The weight of the placenta is one of several measurements that are easy to acquire, and when recorded in a systematic fashion, provide information not just on an individual, but also on a population basis. Birth weights have increased over the last century, and this study provides national data helping distinction between placental physiology and pathology.

Human Placenta Blood Flow During Early Gestation With Pseudocontinuous Arterial Spin Labeling MRI

BACKGROUND

Noninvasive measurement of placental blood flow is the major technical challenge for predicting ischemic placenta (IPD). Pseudocontinuous arterial spin labeling (pCASL) MRI was recently shown to be promising, but the potential value in predicting the subsequence development of IPD is not known.

PURPOSE

To derive global and regional placental blood flow parameters from longitudinal measurements of pCASL MRI and to assess the associations between perfusion-related parameters and IPD.

STUDY TYPE

Prospective.

POPULATION

Eighty-four women completed two pCASL MRI scans (first; 14-18 weeks and second; 19-24 weeks) from prospectively recruited 118 subjects. A total of 69 subjects were included for the analysis, of which 15 subjects developed IPD.

FIELD STRENGTH/SEQUENCE

3T/T₂ -weighted half-Fourier single-shot turbo spin-echo (HASTE) and pCASL.

ASSESSMENT

Four perfusion-related parameters in the placenta were derived: placenta volume, placental blood flow (PBF), high PBF (hPBF), and relative hPBF. The longitudinal changes of the parameters and their association with IPD were tested after being normalizing to the 16th and 20th weeks of gestation.

STATISTICAL TESTS

Comparisons between two gestational ages within subjects were performed using the paired Wilcoxon tests, and comparisons between normal and IPD groups were performed using the unpaired Wilcoxon tests.

RESULTS

The difference between the first and second MRI scans was statistically significant for volume (156.6 cm³ vs. 269.7 cm³ , P < 0.001) and PBF (104.9 ml/100g/min vs. 111.3 ml/100g/min, P = 0.02) for normal subjects, indicating an increase in pregnancy with advancing gestation. Of the parameters tested, the difference between the normal and IPD subjects was most pronounced in hPBF (278.1 ml/100g/min vs. 180.7 ml/100g/min, P < 0.001) and relative hPBF (259.1% vs. 183.2%, P < 0.001) at 16 weeks.

DATA CONCLUSION

The high perfusion-related image parameters for IPD were significantly decreased from normal pregnancy at 14-18 weeks of gestation.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 1 J. Magn. Reson. Imaging 2020;51:1247-1257.

A new customised placental weight standard redefines the relationship between maternal obesity and extremes of placental size and is more closely associated with pregnancy complications than an existing population standard

Placental weight is a valuable indicator of its function, predicting both pregnancy outcome and lifelong health. Population-based centile charts of weight-for-gestational-age and parity are useful for identifying extremes of placental weight but fail to consider maternal size. To address this deficit, a multiple regression model was fitted to derive coefficients for predicting normal placental weight using records from healthy pregnancies of nulliparous/multiparous women of differing height and weight (n = 107,170 deliveries, 37-43 weeks gestation). The difference between actual and predicted placental weight generated a z-score/individual centile for the entire cohort including women with pregnancy complications (n = 121,591). The association between maternal BMI and placental weight extremes defined by the new customised versus population-based standard was investigated by logistic regression, as was the association between low placental weight and pregnancy complications. Underweight women had a greater risk of low placental weight [<10thcentile, OR 1.84 (95% CI 1.66, 2.05)] and obese women had a greater risk of high placental weight [>90th centile, OR 1.98 (95% CI 1.88, 2.10)] using a population standard. After customisation, the risk of high placental weight in obese/morbidly obese women was attenuated [OR 1.17 (95% CI 1.09, 1.25)]/no longer significant, while their risk of low placental weight was 59%-129% higher (P < 0.001). The customised placental weight standard was more closely associated with stillbirth, hypertensive disease, placental abruption and neonatal death than the population standard. Our customised placental weight standard reveals higher risk of relative placental growth restriction leading to lower than expected birthweights in obese women, and a stronger association between low placental weight and pregnancy complications generally. Further, it provides an alternative tool for defining placental weight extremes with implications for the placental programming of chronic disease.

Global population variation in placental size and structure: Evidence from Cebu, Philippines

INTRODUCTION

Placental morphology influences the intrauterine environment and fetal growth, which help set life-course health trajectories across generations. Little is known about placental characteristics in populations with chronic nutritional insufficiency where birth weights tend to be lower, and how these relationships between birth and placental weights vary across populations.

METHODS

We collected weights and stereologically-determined villous mass and surface area of 21 placentas from offspring of women enrolled in a birth cohort study in metropolitan Cebu, Philippines, a low-income population. We identified 15 samples from other global populations ranging from low to high income that had similar data to ours to assess patterns of variation between birth and placental weights and microscopic characteristics. We ranked the population samples in order for each characteristic.

RESULTS

Mean birth weight in Cebu was 3162 ± 80 g (ranked 9/16) and placental weight was 454 ± 32 g (ranked 12/16). Birth:placental weight ratio was 7.0 (ranked 3/16). Average villous surface area for Cebu placentas was 6.5 m2 (ranked 9/12); Birth weight:villous surface area was 0.048 g/m2 (ranked 4/12).

DISCUSSION

Placentas from Cebu produced heavier neonates per units of placental weight and villous surface area than most other populations, despite lower villous surface areas and less complex surface-to-volume topography. This range of placental efficiency spurs questions about the mechanisms by which placental morphology optimizes efficiency in different environmental contexts during gestation. Placental variation both within and across populations is likely due to many intersecting environmental, metabolic, and (epi)genetic factors that will require additional research to clarify.

The transgenerational transmission of maternal adverse childhood experiences (ACEs): Insights from placental aging and infant autonomic nervous system reactivity

OBJECTIVE

To test alterations in placental cellular aging as one pathway by which maternal early adversity influences physiologic development in her offspring.

METHODS

Maternal report of her adverse childhood experiences (ACE) was obtained prenatally along with measures of prenatal stress and demographic information. Placentas (N = 67) were collected at birth and telomere length (TL) was measured in four separate fetally-derived placental tissues: amnion, chorion, villus, and umbilical cord. At four months of age, infants completed the still-face paradigm (SFP) during which respiratory sinus arrhythmia (RSA) data were collected; RSA reactivity and RSA recovery was available from 44 and 41 infants respectively. Multi-level mixed effects models examined the impact of maternal ACE score on placental TL. Generalized linear models tested the relation between composite placental TL and infant RSA, as well as the moderation of maternal ACE score and infant RSA by composite placental TL.

RESULTS

Higher maternal ACE score significantly predicted shorter placental TL across tissues (β = -0.015; P = 0.036) and infant RSA across the SFP. No direct relation was found between placental TL and RSA, however composite placental TL moderated the relation between ACE score and both infant RSA reactivity (β = 0.025; P = 0.005) and RSA recovery (β = -0.028; P = 0.032). In infants with shorter composite placental TL, higher ACE score predicted greater RSA suppression during the still-face epoch relative to play period 1 and greater RSA augmentation during play period 2 relative to the still-face epoch.

CONCLUSIONS

These data are the first, to our knowledge, to report that changes in placental TL influence the transgenerational impact of maternal early life adversity on the development of her offspring's autonomic nervous system.

Hemochorial placentation: development, function, and adaptations

Placentation is a reproductive adaptation that permits fetal growth and development within the protected confines of the female reproductive tract. Through this important role, the placenta also determines postnatal health and susceptibility to disease. The hemochorial placenta is a prominent feature in primate and rodent development. This manuscript provides an overview of the basics of hemochorial placental development and function, provides perspectives on major discoveries that have shaped placental research, and thoughts on strategies for future investigation.

The placental transcriptome of the first-trimester placenta is affected by in vitro fertilization and embryo transfer

BACKGROUND

The placenta is a highly specialized temporary organ that is related to fetal development and pregnancy outcomes, and epidemiological data demonstrate an increased risk of placental abnormality after in vitro fertilization and embryo transfer (IVF-ET).

METHODS

This study examines alterations in the transcriptome profile of first-trimester placentas from IVF-ET pregnancies and analyzes the potential mechanisms that play a role in the adverse perinatal outcomes associated with IVF-ET procedures. Four human placental villi from first-trimester samples were obtained through fetal bud aspiration from patients subjected to IVF-ET due to oviductal factors. An additional four control human placental villi were derived from a group of subjects who spontaneously conceived a twin pregnancy. We analyzed their transcriptomes by microarray. Then, RT-qPCR and immunohistochemistry were utilized to analyze several dysregulated genes to validate the microarray results. Biological functions and pathways were analyzed with bioinformatics tools.

RESULTS

A total of 3405 differentially regulated genes were identified as significantly dysregulated (> 2-fold change; P < 0.05) in the IVF-ET placenta in the first trimester: 1910 upregulated and 1495 downregulated genes. Functional enrichment analysis of the differentially regulated genes demonstrated that the genes were involved in more than 50 biological processes and pathways that have been shown to play important roles in the first trimester in vivo. These pathways can be clustered into coagulation cascades, immune response, transmembrane signaling, metabolism, cell cycle, stress control, invasion and vascularization. Nearly the same number of up- and downregulated genes participate in the same biological processes related to placental development and maintenance. Procedures utilized in IVF-ET altered the expression of first-trimester placental genes that are critical to these biological processes and triggered a compensatory mechanism during early implantation in vivo.

CONCLUSION

These data provide a potential basis for further analysis of the higher frequency of adverse perinatal outcomes following IVF-ET, with the ultimate goal of developing safer IVF-ET protocols.

Adverse Maternal Metabolic Intrauterine Environment and Placental Epigenetics: Implications for Fetal Metabolic Programming

PURPOSE OF REVIEW

Herein, we summarize existent epidemiological studies relating adverse maternal metabolic environments of maternal obesity and gestational diabetes and placental DNA methylation.

RECENT FINDINGS

Multiple studies have evaluated associations between intrauterine exposure to gestational diabetes and/or maternal glucose levels and DNA methylation at candidate metabolic genes as well as in epigenome-wide studies. Some of the genomic regions more consistently associated include lipid-related genes (LPL and PPARGC1A), the major histocompatibility complex (MHC), and imprinted genes. Studies solely focused on maternal obesity influences on the placental epigenome are scarce. Understanding the placental mechanisms involved in fetal metabolic programming could lead to discovery of placental biomarkers at birth that predict later-life metabolic risk. Moving forward is important to standardize methods utilized in epigenetics research; consistent methodology can help interpret disparate findings. Larger studies with longitudinal follow-up are needed to address future challenges in fetal programming research.

Placental thickness on ultrasound and neonatal birthweight

Objective To investigate the relationship between maximal placental thickness during routine anatomy scan and birthweight at delivery. Methods This retrospective descriptive study analyzed 200 term, singleton deliveries in 2016 at Penn State Hershey Medical Center. We measured maximal placental thickness in the sagittal plane from the ultrasound images of the placenta obtained at the 18-21-week fetal anatomy screen. The relationship between placental thickness and neonatal birthweight was assessed using Pearson's correlation coefficient (r) with 95% confidence interval (CI). Logistic regression was used to assess the association between placental thickness and secondary binary outcomes of neonatal intensive care unit (NICU) admission and poor Apgar scores. Two-sample t-tests, or exact Wilcoxon rank-sum test for non-normally distributed data, were used to assess for differences attributable to medical comorbidities (pre-gestational diabetes, gestational diabetes, chronic hypertension, gestational hypertension, preeclampsia and eclampsia). Results Placental thickness had a positive correlation with neonatal birthweight [r=0.18, 95% CI=(0.05, 0.32)]. The mean placental thickness measured 34.2±9.7 mm. The strength of the correlation remained similar when adjusting for gestational age (r=0.20) or excluding medical comorbidities (r=0.19). There was no association between placental thickness and NICU admission, Apgar scores <7 or medical comorbidities. Conclusion Our study demonstrated a positive correlation between sonographic placental thickness and birthweight. Future prospective studies are warranted in order to further investigate whether a clinically significant correlation exists while adjusting for more covariates.

Texture analysis of magnetic resonance images of the human placenta throughout gestation: A feasibility study

As fetal gestational age increases, other modalities such as ultrasound have demonstrated increased levels of heterogeneity in the normal placenta. In this study, we introduce and apply ROI-based texture analysis to a retrospective fetal MRI database to characterize the second-order statistics of placenta and to evaluate the relationship between heterogeneity and gestational age. Positive correlations were observed for several Haralick texture metrics derived from fetal-brain specific T2-weighted and gravid uterus T1-weighted and T2-weighted images, confirming a quantitative increase in placental heterogeneity with gestational age. Our study shows the importance of identifying baseline MR textural changes at certain gestational ages from which placental diseased states may be compared. Specifically, when evaluating for placental invasion or insufficiency, findings should be evaluated in the context of the normal placental aging process, which occurs throughout gestation.

Trophoblastic microRNAs are downregulated in a diabetic pregnancy through an inhibition of Drosha

MicroRNAs are promising biological markers for prenatal diagnosis. They regulate placental development and are present in maternal plasma. Maternal metabolic diseases are major risk factors for placental deterioration. We analysed the influence of a maternal insulin-dependent diabetes mellitus on microRNA expression in maternal plasma and in blastocysts employing an in vivo rabbit diabetic pregnancy model and an in vitro embryo culture in hyperglycaemic and hypoinsulinaemic medium. Maternal diabetes led to a marked downregulation of Dicer protein in embryoblast cells and Drosha protein in trophoblast cells. MiR-27b, miR-141 and miR-191 were decreased in trophoblast cells and in maternal plasma of diabetic rabbits. In vitro studies indicate, that maternal hyperglycaemia and hypoinsulinaemia partially contribute to the downregulation of trophoblastic microRNAs. As the altered microRNA expression was detectable in maternal plasma, too, the plasma microRNA signature could serve as an early biological marker for the prediction of trophoblast function during a diabetic pregnancy.

Birth weight and adolescent blood pressure measured at age 12 years in the Gateshead Millennium Study

Birth weight and early growth have been associated with later blood pressure. However, not all studies consistently find a significant reduction in blood pressure with an increase in birth weight. In addition, the relative importance of birth weight and of other lifestyle and environmental factors is often overlooked and the association is rarely studied in adolescents. We investigated early life predictors, including birth weight, of adolescent blood pressure in the Gateshead Millennium Study (GMS). The GMS is a cohort of 1029 individuals born in 1999-2000 in Gateshead in Northern England. Throughout infancy and early childhood, detailed information were collected, including birth weight and measures of height and weight. Assessments of 491 returning participants at age 12 years included measures of body mass and blood pressure. Linear regression and path analysis were used to determine predictors and their relative importance on blood pressure. Birth weight was not directly associated with blood pressure at the age of 12. However, after adjustment for contemporaneous body mass index (BMI), an inverse association of standardized birth weight on systolic blood pressure was significant. The relative importance of birth weight on later systolic blood pressure was smaller than other contemporaneous body measures (height and BMI). There was no independent association of birth weight on blood pressure seen in this adolescent population. Contemporaneous body measures have an important role to play. Lifestyle factors that influence body mass or size, such as diet and physical activity, where interventions are directed at early prevention of hypertension should be targeted.

Children's untreated decay is positively associated with past caries experience and with current salivary loads of mutans Streptococci; negatively with self-reported maternal iron supplements during pregnancy: a multifactorial analysis

OBJECTIVES

This study explored the association of children's salivary characteristics, past caries experience, birth weight, and reported maternal prenatal vitamin and mineral supplementation with the dental untreated decay of the child.

METHODS

This cross-sectional study, a sub-study of Griffith University Environments for Healthy Living birth cohort study, was conducted on 174 mother-child dyads. Mother's prenatal usage of vitamin and mineral supplements; child's birthweight; salivary pH, buffering capacity, and levels of salivary MS and LB were explored as risk indicators. Dental caries experience was assessed using International Caries Detection and Assessment System criteria. Path analysis was conducted to evaluate the association of risk indicators with children's current and past dental caries experience.

RESULTS

Children's past caries experience (β = 0.332, p = 0.018), and salivary MS counts (β = 0.215, p = 0.032) were positively associated with untreated decay at time of examination. With a trend towards significance, children whose mothers had reported taking iron supplements during pregnancy experienced lower levels of past caries (β = -0.137, p = 0.068) and untreated dental caries (β = -0.046, p = 0.051).

CONCLUSIONS

This study confirms that a child's levels of untreated decay is positively associated with their past caries, and that it correlates with current levels of salivary MS. Children of mothers who reported to have taken iron supplements during pregnancy experienced less caries throughout their lives. These observations confirm the importance to offspring of monitoring maternal health throughout pregnancy and of early monitoring of children's oral health in preventing future dental disease.

Moving beyond individual choice in policies to reduce health inequalities: the integration of dynamic with individual explanations

Background

A strong focus on individual choice and behaviour informs interventions designed to reduce health inequalities in the UK. We review evidence for wider mechanisms from a range of disciplines, demonstrate that they are not yet impacting on programmes, and argue for their systematic inclusion in policy and research.

Methods

We identified potential mechanisms relevant to health inequalities and their amelioration from different disciplines and analysed six policy documents published between 1976 and 2010 using Bacchi's 'What's the problem represented to be?' framework for policy analysis.

Results

We found substantial evidence of supra-individualistic and relational mechanisms relevant to health inequalities from sociology, history, biology, neuroscience, philosophy and psychology. Policy documents sometimes expressed these mechanisms in policy rhetoric but rarely in policy recommendations, which continue to focus on individual behaviour.

Discussion

Current evidence points to the potential of systematically applying broader thinking about causal mechanisms, beyond individual choice and responsibility, to the design, implementation and evaluation of policies to reduce health inequalities. We provide a set of questions designed to enable critique of policy discussions and programmes to ensure that these wider mechanisms are considered.

Genetic variants influence on the placenta regulatory landscape

From genomic association studies, quantitative trait loci analysis, and epigenomic mapping, it is evident that significant efforts are necessary to define genetic-epigenetic interactions and understand their role in disease susceptibility and progression. For this reason, an analysis of the effects of genetic variation on gene expression and DNA methylation in human placentas at high resolution and whole-genome coverage will have multiple mechanistic and practical implications. By producing and analyzing DNA sequence variation (n = 303), DNA methylation (n = 303) and mRNA expression data (n = 80) from placentas from healthy women, we investigate the regulatory landscape of the human placenta and offer analytical approaches to integrate different types of genomic data and address some potential limitations of current platforms. We distinguish two profiles of interaction between expression and DNA methylation, revealing linear or bimodal effects, reflecting differences in genomic context, transcription factor recruitment, and possibly cell subpopulations. These findings help to clarify the interactions of genetic, epigenetic, and transcriptional regulatory mechanisms in normal human placentas. They also provide strong evidence for genotype-driven modifications of transcription and DNA methylation in normal placentas. In addition to these mechanistic implications, the data and analytical methods presented here will improve the interpretability of genome-wide and epigenome-wide association studies for human traits and diseases that involve placental functions.

The placenta is a critical organ playing multiple roles including oxygen and metabolite transfer from mother to fetus, hormone production, and vascular perfusion. With this study, we aimed to deliver a placenta-specific regulatory map based on a combination of publicly available and newly generated data. To complete this reference, we obtained genotype information (n = 303), DNA methylation (n = 303) and expression data (n = 80) for placentas from healthy women. Our analysis of methylation and expression quantitative trait loci (QTLs) and correlations between methylation and expression data were designed to identify fundamental associations between genome, transcriptome, and epigenome in this key fetal organ. The results provide high-resolution genetic and epigenetic maps specific to the placenta based on a representative ethnically diverse cohort. As interest and efforts are growing to better understand the etiology of placental disease and the impact of the environment on placental function these data will provide a reference and enhance future investigations.

Maternal stress and placental function, a study using questionnaires and biomarkers at birth

Background

Prenatal stress affects the health of the pregnant woman and the fetus. Cortisol blood levels are elevated in pregnancy, and fetal exposure to cortisol is regulated by the placenta enzyme 11β-HSD2. A decrease in enzyme activity allows more maternal cortisol to pass through the placental barrier. Combining the fetal and maternal cortisol to cortisone ratio into the adjusted fetal cortisol exposure (AFCE) represents the activity of the enzyme 11β-HSD2 in the placenta.

Aim

To investigate the effect of prenatal maternal stress on the ratio of cortisol and cortisone in maternal and fetal blood at birth in a normal population.

Method

Maternal self-reported stress was assessed at one time-point, as late in the pregnancy as convenient for the participant, using the Depression Anxiety Stress Scales (DASS-42), Pregnancy Related Anxiety (PRA), and Major Life Events during pregnancy. The study included 273 participants from Copenhagen University Hospital. Maternal and umbilical cord blood was sampled directly after birth and cortisol and cortisone concentrations were quantified using UPLC chromatography. Data were analyzed in a five-step regression model with addition of possible confounders. The primary outcome was AFCE, and plasma concentrations of maternal and fetal cortisol and cortisone were secondary outcomes.

Results

Significant associations were seen for the primary outcome AFCE and the plasma concentrations of maternal cortisol and fetal cortisone with exposure to Pregnancy Related Anxiety (PRA), though the associations were reduced when adjusting for birth related variables, especially delivery mode. The weight of the placenta affected the associations of exposures on AFCE, but not plasma concentrations of cortisol and cortisone in mother and fetus. Moreover, the study demonstrated the importance of delivery mode and birth strain on cortisol levels right after delivery.

Conclusion

Our main finding was associations between PRA and AFCE, which shows the effect of maternal stress on placental cortisol metabolism.

How well do national and local policies in England relevant to maternal and child health meet the international standard for non-communicable disease prevention? A policy analysis

OBJECTIVES

(1) To identify national policies for England and local policies for Southampton City that are relevant to maternal and child health. (2) To quantify the extent to which these policies meet the international standards for nutrition and physical activity initiatives set out in the WHO Global Action Plan for the Prevention and Control of Non-Communicable Diseases (WHO Action Plan).

DESIGN

The policy appraisal process involved three steps: (1) identifying policy documents relevant to maternal and infant health, (2) developing a policy appraisal framework from the WHO Action Plan, and (3) analysing the policies using the framework.

SETTING

England and Southampton City.

PARTICIPANTS

57 national and 10 local policies.

RESULTS

Across both national and local policies, priority areas supporting public health processes, such as evidence-based practice, were adopted more frequently than the action-oriented areas targeting maternal and child dietary and physical activity behaviours. However, the policy option managing conflicts of interest was rarely considered in the national policies (12%), particularly in white papers or evidence-based guidelines. For the action-oriented priority areas, maternal health policy options were more frequently considered than those related to child health or strengthening health systems. Complementary feeding guidance (9%) and workforce training in empowerment skills (14%) were the least frequent action-oriented policy options adopted among the national policies. The maternal nutrition-focused and workforce development policy options were least frequent among local policies adopted in 10% or fewer. Macroenvironmental policy options tended to have a lower priority than organisational or individual options among national policies (p=0.1) but had higher priority among local policies (p=0.02).

CONCLUSIONS

Further action is needed to manage conflicts of interest and adopt policy options that promote a system-wide approach to address non-communicable diseases caused by poor diet and physical inactivity.

Emerging insights into hypothalamic-pituitary-gonadal axis regulation and interaction with stress signalling

Reproduction and fertility are regulated via hormones of the hypothalamic-pituitary-gonadal (HPG) axis. Control of this reproductive axis occurs at all levels, including the brain and pituitary, and allows for the promotion or inhibition of gonadal sex steroid secretion and function. In addition to guiding proper gonadal development and function, gonadal sex steroids also act in negative- and positive-feedback loops to regulate reproductive circuitry in the brain, including kisspeptin neurones, thereby modulating overall HPG axis status. Additional regulation is also provided by sex steroids made within the brain, including neuroprogestins. Furthermore, because reproduction and survival need to be coordinated and balanced, the HPG axis is able to modulate (and be modulated by) stress hormone signalling, including cortiscosterone, from the hypothalamic-pituitary-adrenal (HPA) axis. This review covers recent data related to the neural, hormonal and stress regulation of the HPG axis and emerging interactions between the HPG and HPA axes, focusing on actions at the level of the brain and pituitary.

Delayed Cord Clamping in Infants with Suspected Intrauterine Growth Restriction

We evaluated a subset of infants with suspected intrauterine growth restriction or birth weights small for gestational age enrolled in a study of delayed cord clamping for preterm infants. Compared with immediate clamping, delayed cord clamping was associated with no apparent harm and less suspected necrotizing enterocolitis.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00818220 and NCT01426698.

Physiology and Pathophysiology of Steroid Biosynthesis, Transport and Metabolism in the Human Placenta

The steroid hormones progestagens, estrogens, androgens, and glucocorticoids as well as their precursor cholesterol are required for successful establishment and maintenance of pregnancy and proper development of the fetus. The human placenta forms at the interface of maternal and fetal circulation. It participates in biosynthesis and metabolism of steroids as well as their regulated exchange between maternal and fetal compartment. This review outlines the mechanisms of human placental handling of steroid compounds. Cholesterol is transported from mother to offspring involving lipoprotein receptors such as low-density lipoprotein receptor (LDLR) and scavenger receptor class B type I (SRB1) as well as ATP-binding cassette (ABC)-transporters, ABCA1 and ABCG1. Additionally, cholesterol is also a precursor for placental progesterone and estrogen synthesis. Hormone synthesis is predominantly performed by members of the cytochrome P-450 (CYP) enzyme family including CYP11A1 or CYP19A1 and hydroxysteroid dehydrogenases (HSDs) such as 3β-HSD and 17β-HSD. Placental estrogen synthesis requires delivery of sulfate-conjugated precursor molecules from fetal and maternal serum. Placental uptake of these precursors is mediated by members of the solute carrier (SLC) family including sodium-dependent organic anion transporter (SOAT), organic anion transporter 4 (OAT4), and organic anion transporting polypeptide 2B1 (OATP2B1). Maternal-fetal glucocorticoid transport has to be tightly regulated in order to ensure healthy fetal growth and development. For that purpose, the placenta expresses the enzymes 11β-HSD 1 and 2 as well as the transporter ABCB1. This article also summarizes the impact of diverse compounds and diseases on the expression level and activity of the involved transporters, receptors, and metabolizing enzymes and concludes that the regulatory mechanisms changing the physiological to a pathophysiological state are barely explored. The structure and the cellular composition of the human placental barrier are introduced. While steroid production, metabolism and transport in the placental syncytiotrophoblast have been explored for decades, few information is available for the role of placental-fetal endothelial cells in these processes. With regard to placental structure and function, significant differences exist between species. To further decipher physiologic pathways and their pathologic alterations in placental steroid handling, proper model systems are mandatory.

The frequency and type of placental histologic lesions in term pregnancies with normal outcome

Objective To determine the frequency and type of histopathologic lesions in placentas delivered by women with a normal pregnancy outcome. Methods This retrospective cohort study included placental samples from 944 women with a singleton gestation who delivered at term without obstetrical complications. Placental lesions were classified into the following four categories as defined by the Society for Pediatric Pathology and by our unit: (1) acute placental inflammation, (2) chronic placental inflammation, (3) maternal vascular malperfusion and (4) fetal vascular malperfusion. Results (1) Seventy-eight percent of the placentas had lesions consistent with inflammatory or vascular lesions; (2) acute inflammatory lesions were the most prevalent, observed in 42.3% of the placentas, but only 1.0% of the lesions were severe; (3) acute inflammatory lesions were more common in the placentas of women with labor than in those without labor; (4) chronic inflammatory lesions of the placenta were present in 29.9%; and (5) maternal and fetal vascular lesions of malperfusion were detected in 35.7% and 19.7%, respectively. Two or more lesions with maternal or fetal vascular features consistent with malperfusion (high-burden lesions) were present in 7.4% and 0.7%, respectively. Conclusion Most placentas had lesions consistent with inflammatory or vascular lesions, but severe and/or high-burden lesions were infrequent. Mild placental lesions may be interpreted either as acute changes associated with parturition or as representative of a subclinical pathological process (intra-amniotic infection or sterile intra-amniotic inflammation) that did not affect the clinical course of pregnancy.

The Chinese Children and Families Cohort Study: The Nutrition, Physical Activity, and Ultraviolet Radiation Data Collection

This article reports the study design, methodological issues and early results of a pilot study testing methods for collecting nutrition, physical activity, and ultraviolet (UV) radiation exposure data in a groundbreaking study in China. Epidemiological studies suggest that exposures across the entire life course, including in utero, early childhood, and adolescence, may be important in the etiology of adult cancers and other chronic diseases. The Chinese Children and Families Cohort Study intends to follow-up subjects from the 1993 to 1995 Community Intervention Program of folic acid supplementation for the prevention of neural tube defects. This cohort is unique in that only folic acid exposure during pregnancy varies between groups as other supplements were not available, and there were nutrient deficiencies in the populations. Prior to launching a large-scale follow-up effort, a pilot study was conducted to assess the feasibility of recontacting original study participants to collect extensive diet, physical activity, and UV radiation exposure data in this population. The pilot study included 92 mothers and 184 adolescent children aged 14 to 17 years from 1 urban and 1 rural Community Intervention Program site. Subjects completed a Food Frequency Questionnaire, a 3-day food record, a physical activity questionnaire, a 3-day sun exposure diary together with 3 days of personal UV dosimetry, and 7 days of pedometry measurements and provided blood, saliva, and toenail samples. Grip strength and body composition measurements were taken, and ambient solar UV radiation was monitored in both study sites. While most of the assessments were successful, future studies would likely require different dietary intake instruments. The purpose of this report is to describe the study design and methodological issues emerging from this pilot work relevant for the follow-up of this large birth cohort.

Family lifestyle dynamics and childhood obesity: evidence from the millennium cohort study

Background

The prevalence of childhood obesity has been increasing but the causes are not fully understood. Recent public health interventions and guidance aiming to reduce childhood obesity have focused on the whole family, as opposed to just the child but there remains a lack of empirical evidence examining this relationship.

Methods

Using data from the longitudinal Millennium Cohort Study (MCS), we investigate the dynamic relationship between underlying family lifestyle and childhood obesity during early childhood. The MCS interviewed parents shortly after the birth of their child and follow up interviews were carried out when the child was 3, 5 and 7 years. We use a dynamic latent factor model, an approach that allows us to identify family lifestyle, its evolution over time (in this case between birth and 7 years) and its influence on childhood obesity and other observable outcomes.

Results

We find that family lifestyle is persistent, 87.43% of families which were above the 95th percentile on the lifestyle distribution, remained above the 95th percentile when the child was 7 years old. Family lifestyle has a significant influence on all outcomes in the study, including diet, exercise and parental weight status; family lifestyle accounts for 11.3% of the variation in child weight by age 7 years.

Conclusion

The analysis suggests that interventions should therefore be prolonged and persuasive and target the underlying lifestyle of a family as early as possible during childhood in order to have the greatest cumulative influence. Our results suggest that children from advantaged backgrounds are more likely to be exposed to healthier lifestyles and that this leads to inequalities in the prevalence of obesity. To reduce inequalities in childhood obesity, policy makers should target disadvantaged families and design interventions specifically for these families.

Screening for fetal growth restriction and placental insufficiency

Fetal growth restriction (FGR) continues to be a leading cause of preventable stillbirth and poor neurodevelopmental outcomes in offspring, and furthermore is strongly associated with the obstetrical complications of iatrogenic preterm birth and pre-eclampsia. The terms small for gestational age (SGA) and FGR have, for too long, been considered equivalent and therefore used interchangeably. However, the delivery of improved clinical outcomes requires that clinicians effectively distinguish fetuses that are pathologically growth-restricted from those that are constitutively small. A greater understanding of the multifactorial pathogenesis of both early- and late-onset FGR, especially the role of underlying placental pathologies, may offer insight into targeted treatment strategies that preserve placental function. The new maternal blood biomarker placenta growth factor offers much potential in this context. This review highlights new approaches to effective screening for FGR based on a comprehensive review of: etiology, diagnosis, antenatal surveillance and management. Recent advances in novel imaging methods provide the basis for stepwise multi-parametric testing that may deliver cost-effective screening within existing antenatal care systems.

Prevalence of xenobiotic substances in first-trimester blood samples from Danish pregnant women: a cross-sectional study

OBJECTIVE

The aim of this study was to investigate the prevalence of xenobiotic substances, such as caffeine, nicotine and illicit drugs (eg, cannabis and cocaine), in blood samples from first-trimester Danish pregnant women unaware of the screening.

DESIGN

A cross-sectional study examined 436 anonymised residual blood samples obtained during 2014 as part of the nationwide prenatal first-trimester screening programme. The samples were analysed by ultra performance liquid chromatography with high-resolution time-of-flight mass spectrometry.

SETTING

An antenatal clinic in a Danish city with 62 000 inhabitants, where >95% of pregnant women joined the screening programme.

PRIMARY AND SECONDARY OUTCOME MEASURES

The prevalence and patterns of caffeine, nicotine, medication and illicit drug intake during the first trimester of pregnancy.

RESULTS

The prevalence of prescription and over-the-counter drug detection was 17.9%, including acetaminophen (8.9%) and antidepressants (3.0%), of which citalopram (0.9%) was the most frequent. The prevalence of illegal drugs, indicators of smoking (nicotine/cotinine) and caffeine was 0.9%, 9.9%, and 76.4%, respectively. Only 17.4% of women had no substance identified in their sample.

CONCLUSIONS

This study emphasises the need for further translational studies investigating lifestyle habits during pregnancy, as well as the underlying molecular mechanisms through which xenobiotic substances may affect placental function and fetal development.

Placental Morphology Is Associated with Maternal Depressive Symptoms during Pregnancy and Toddler Psychiatric Problems

Maternal depressive symptoms during pregnancy predict increased psychiatric problems in children. The underlying biological mechanisms remain unclear. Hence, we examined whether alterations in the morphology of 88 term placentas were associated with maternal depressive symptoms during pregnancy and psychiatric problems in 1.9-3.1-years old (Mean = 2.1 years) toddlers. Maternal depressive symptoms were rated biweekly during pregnancy with the Center of Epidemiological Studies Depression Scale (n = 86). Toddler psychiatric problems were mother-rated with the Child Behavior Checklist (n = 60). We found that higher maternal depressive symptoms throughout pregnancy [B = -0.24 Standard Deviation (SD) units: 95% Confidence Interval (CI) = -0.46; -0.03: P = 0.03; Mean difference = -0.66 SDs; 95% CI = -0.08; -1.23: P = 0.03; between those with and without clinically relevant depressive symptoms] were associated with lower variability in the placental villous barrier thickness of γ-smooth muscle actin-negative villi. This placental morphological change predicted higher total (B = -0.34 SDs: 95% CI = -0.60; -0.07: P = 0.01) and internalizing (B = -0.32 SDs: 95% CI = -0.56; -0.08: P = 0.01) psychiatric problems in toddlers. To conclude, our findings suggest that both maternal depressive symptoms during pregnancy and toddler psychiatric problems may be associated with lower variability in the villous membrane thickness of peripheral villi in term placentas. This lower heterogeneity may compromise materno-fetal exchange, suggesting a possible role for altered placental morphology in the fetal programming of mental disorders.