Placenta-Specific Transcripts Containing Androgen Response Elements Are Altered In Silico by Male Growth Outcomes.

A birthweight centile (BWC) below the 25th is associated with an elevated risk of adverse perinatal outcomes, particularly among males. This male vulnerability may stem from alterations in placenta-specific androgen signalling, a signalling axis that involves the androgen receptor (AR)-mediated regulation of target genes containing androgen response elements (AREs). In this study, we examined global and ARE-specific transcriptomic signatures in term male placentae (≥37 weeks of gestation) across BWC subcategories (<10th, 10th-30th, >30th) using RNA-seq and gene set enrichment analysis. ARE-containing transcripts in placentae with BWCs below the 10th percentile were upregulated compared to those in the 10th-30th and >30th percentiles, which coincided with the enrichment of gene sets related to hypoxia and the suppression of gene sets associated with mitochondrial function. In the absence of ARE-containing transcripts in silico, <10th and 10th-30th BWC subcategory placentae upregulated gene sets involved in vasculature development, immune function, and cell adhesion when compared to those in the >30th BWC subcategory. Collectively, our in silico findings suggest that changes in the expression of ARE-containing transcripts in male placentae may contribute to impaired placental vasculature and therefore result in reduced fetal growth outcomes.

Anxiety and Depression in Early Gestation and the Association with Subsequent Gestational Diabetes Mellitus in a Disadvantaged Population.

OBJECTIVES: Evaluate the association between poor mental health and risk of developing gestational diabetes mellitus (GDM) in a cohort of women from a socioeconomically disadvantaged community. METHODS: A total of 1363 nulliparous women with singleton pregnancies recruited to the Screening Tests to Predict Poor Outcomes of Pregnancy study in Adelaide, Australia. Women were assessed for mental health in the first trimester, including likelihood of depression, high functioning anxiety, perceived stress and risk of developing a mental health disorder. GDM was diagnosed based on the International Association of Diabetes in Pregnancy Study Group (IADPSG) criteria. Socioeconomic status was measured using the New Zealand Socioeconomic Index (NZSEI). RESULTS: Complete mental health data was available for 1281 participants. There was no statistically significant difference in SEI, depression, risk of mental health issues, high functioning anxiety and perceived stress between women who developed GDM and those who did not. There was no difference in history of depression nor risk of developing a high mental health disorder in first trimester after adjusting for SEI, BMI in first trimester, smoking status in first trimester and maternal age between women with a GDM pregnancy and those who did not. CONCLUSIONS FOR PRACTICE: There was no difference in markers of poor mental health in early pregnancy between women who subsequently did or did not develop GDM. Cohort participants were socioeconomically disadvantaged, potentially contributing to the lack of apparent differences in depression observed between groups. Socioeconomically disadvantaged women should be targeted in pre-conception planning to reduce risk of GDM.

A prospective registry analysis of psychosocial and metabolic health between women with and without metabolic syndrome after a complicated pregnancy.

PURPOSE: Pregnancy complications affect over one quarter of Australian pregnancies, and this group of mothers is vulnerable and more likely to experience adverse cardiometabolic health outcomes in the postpartum period. Metabolic syndrome is common in this population and may be associated with postpartum mental health issues. However, this relationship remains poorly understood. To compare the differences in psychosocial parameters and mental health outcomes between women with metabolic syndrome and women without metabolic syndrome 6 months after a complicated pregnancy. METHODS: This study is prospective registry analysis of women attending a postpartum healthy lifestyle clinic 6 months following a complicated pregnancy. Mental health measures included 9-item Patient Health Questionnaire (PHQ-9), 7-item Generalised Anxiety Disorder questionnaire (GAD-7), self-reported diagnosed history of depression, anxiety and/or other psychiatric condition, and current psychotropic medication use. RESULTS: Women with metabolic syndrome reported significantly more subjective mental health concerns, were more likely to have a history of depression and other psychiatric diagnoses and were more likely prescribed psychotropic medications. However, there were no significant differences in PHQ-9 and GAD-7 scores. CONCLUSION: Amongst new mothers who experienced complications of pregnancy, those with metabolic syndrome represent a particularly vulnerable group with regards to psychosocial disadvantage and mental health outcomes. These vulnerabilities may not be apparent when using common standardised cross-sectional mental health screening tools such as PHQ-9 and GAD-7.

Relative importance of metabolic syndrome components for developing gestational diabetes.

PURPOSE: To assess the independent and joint contribution of the individual components of metabolic syndrome, and known risk factors for gestational diabetes (GDM), on risk of GDM. METHODS: Two thousand nine hundred and fifteen women from Australia and New Zealand, who participated in The Screening for Pregnancy Endpoints Study (SCOPE), were included. Using the SCOPE clinical data set and biomarkers obtained at 14-16 weeks' gestation, a logistic regression model was fitted to the binary outcome GDM, with individual metabolic syndrome components (waist circumference, blood pressure, glucose, HDL-C, triglycerides), recruitment site, and other established factors associated with GDM. Hierarchical partitioning was used to assess the relative contribution of each variable. RESULTS: Of the 2915 women, 103 women (3.5%) developed GDM. The deviance explained by the logistic regression model containing all variables was 18.65% and the AUC was 0.809. Seventy percent of the independent effect was accounted for by metabolic syndrome components. The highest independent relative contribution to GDM was circulating triglycerides (17 ± 3%), followed by waist circumference (13 ± 3%). Glucose and maternal BMI contributed 12 ± 2% and 12 ± 3%, respectively. The remaining factors had an independent relative contribution of < 10%. CONCLUSION: Triglyceride concentrations had the highest independent relative importance for risk of GDM. Increased focus for lowering triglycerides as an important risk factor for GDM is warranted.

Circular RNAs in Pregnancy and the Placenta.

The emerging field of circular RNAs (circRNAs) has identified their novel roles in the development and function of many cancers and inspired the interest of many researchers. circRNAs are also found throughout the healthy body, as well as in other pathological states, but while research into the function and abundance of circRNAs has progressed, our overall understanding of these molecules remains primitive. Importantly, recent studies are elucidating new roles for circRNAs in pregnancy, particularly in the placenta. Given that many of the genes responsible for circRNA production in cancer are also highly expressed in the placenta, it is likely that the same genes act in the production of circRNAs in the placenta. Furthermore, placental development can be referred to as 'controlled cancer', as it shares many key signalling pathways and hallmarks with tumour growth and metastasis. Hence, the roles of circRNAs in this field are important to study with respect to pregnancy success but also may provide novel insights for cancer progression. This review illuminates the known roles of circRNAs in pregnancy and the placenta, as well as demonstrating differential placental expressions of circRNAs between complicated and uncomplicated pregnancies.

Placental Transcription Profiling in 6-23 Weeks' Gestation Reveals Differential Transcript Usage in Early Development.

The human placenta is a rapidly developing transient organ that is key to pregnancy success. Early development of the conceptus occurs in a low oxygen environment before oxygenated maternal blood begins to flow into the placenta at ~10-12 weeks' gestation. This process is likely to substantially affect overall placental gene expression. Transcript variability underlying gene expression has yet to be profiled. In this study, accurate transcript expression profiles were identified for 84 human placental chorionic villus tissue samples collected across 6-23 weeks' gestation. Differential gene expression (DGE), differential transcript expression (DTE) and differential transcript usage (DTU) between 6-10 weeks' and 11-23 weeks' gestation groups were assessed. In total, 229 genes had significant DTE yet no significant DGE. Integration of DGE and DTE analyses found that differential expression patterns of individual transcripts were commonly masked upon aggregation to the gene-level. Of the 611 genes that exhibited DTU, 534 had no significant DGE or DTE. The four most significant DTU genes ADAM10, VMP1, GPR126, and ASAH1, were associated with hypoxia-responsive pathways. Transcript usage is a likely regulatory mechanism in early placentation. Identification of functional roles will facilitate new insight in understanding the origins of pregnancy complications.

A sexually dimorphic murine model of IUGR induced by embryo transfer.

Animal models are needed to develop interventions to prevent or treat intrauterine growth restriction (IUGR). Foetal growth rates and effects of in utero exposures differ between sexes, but little is known about sex-specific effects of increasing litter size. We established a murine IUGR model using pregnancies generated by multiple embryo transfers, and evaluated sex-specific responses to increasing litter size. CBAF1 embryos were collected at gestation day 0.5 (GD0.5) and 6, 8, 10 or 12 embryos were transferred into each uterine horn of pseudopregnant female CD1 mice (n = 32). Foetal and placental outcomes were measured at GD18.5. In the main experiment, foetuses were genotyped (Sry) for analysis of sex-specific outcomes. The number of implantation sites (P = 0.033) and litter size (number of foetuses, P = 0.008) correlated positively with the number of embryos transferred, while placental weight correlated negatively with litter size (both P < 0.01). The relationship between viable litter size and foetal weight differed between sexes (interaction P = 0.002), such that foetal weights of males (P = 0.002), but not females (P = 0.233), correlated negatively with litter size. Placental weight decreased with increasing litter size (P < 0.001) and was lower in females than males (P = 0.020). Our results suggest that male foetuses grow as fast as permitted by nutrient supply, whereas the female maintains placental reserve capacity. This strategy reflecting sex-specific gene expression is likely to place the male foetus at greater risk of death in the event of a 'second hit'.

Cardiovascular risk factors in women with previous gestational diabetes mellitus: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to synthesize evidence on conventional cardiovascular disease (CVD) risk factors among women with previous Gestational Diabetes Mellitus (GDM). The review protocol is registered with PROSPERO (CRD42019118149). PubMed, CINAHL, SCOPUS, and EMBASE databases were searched. Studies reporting on CVD risk factors in women with previous GDM compared to women without previous GDM were selected. A total of 139 studies were eligible, of which 93 were included in the meta-analysis. Women with previous GDM have significantly higher systolic blood pressure (2.47 mmHg 95% CI 1.74 to 3.40, n = 48, 50,118 participants) diastolic blood pressure (1.89 mmHg 95% CI 1.32 to 2.46, n = 48, 49,495 participants), BMI (1.54 kg/m2 95% CI 1.32 to 2.46, n = 78, 255,308 participants), total cholesterol (0.26 SMD 95% CI 0.15 to 0.37, n = 48, 38,561 participants), LDL cholesterol (0.19 SMD 95% CI 0.08 to 0.30, n = 44, 16,980 participants), triglycerides (0.56 SMD 95% CI 0.42 to 0.70, n = 46, 13,175 participants), glucose (0.69 SMD 95% CI 0.56 to 0.81, n = 55, 127,900 participants), insulin (0.41 SMD 95% CI 0.23 to 0.59, n = 32, 8881 participants) and significantly lower HDL cholesterol (-0.28 SMD 95% CI -0.39 to -0.16, n = 56, 35,882 participants), compared to women without previous GDM. The increased blood pressure, total cholesterol, triglycerides and glucose are seen as early as <1 year post-partum.Women with previous GDM have a higher risk of CVD based on significant increases in conventional risk factors. Some risk factors are seen as early as <1 year post-partum. Women with GDM may benefit from early screening to identify modifiable CVD risk factors.

Large-scale transcriptome-wide profiling of microRNAs in human placenta and maternal plasma at early to mid gestation.

MicroRNAs (miRNAs) are increasingly seen as important regulators of placental development and opportunistic biomarker targets. Given the difficulty in obtaining samples from early gestation and subsequent paucity of the same, investigation of the role of miRNAs in early gestation human placenta has been limited. To address this, we generated miRNA profiles using 96 placentas from presumed normal pregnancies, across early gestation, in combination with matched profiles from maternal plasma. Placenta samples range from 6 to 23 weeks' gestation, a time period that includes placenta from the early, relatively low but physiological (6-10 weeks' gestation) oxygen environment, and later, physiologically normal oxygen environment (11-23 weeks' gestation).We identified 637 miRNAs with expression in 86 samples (after removing poor quality samples), showing a clear gestational age gradient from 6 to 23 weeks' gestation. We identified 374 differentially expressed (DE) miRNAs between placentas from 6-10 weeks' versus 11-23 weeks' gestation. We see a clear gestational age group bias in miRNA clusters C19MC, C14MC, miR-17 ~ 92 and paralogs, regions that also include many DE miRNAs. Proportional change in expression of placenta-specific miRNA clusters was reflected in maternal plasma.The presumed introduction of oxygenated maternal blood into the placenta (between ~10 and 12 weeks' gestation) changes the miRNA profile of the chorionic villus, particularly in placenta-specific miRNA clusters. Data presented here comprise a clinically important reference set for studying early placenta development and may underpin the generation of minimally invasive methods for monitoring placental health.

Maternal folate, one-carbon metabolism and pregnancy outcomes.

Single nucleotide polymorphisms and pre- and peri-conception folic acid (FA) supplementation and dietary data were used to identify one-carbon metabolic factors associated with pregnancy outcomes in 3196 nulliparous women. In 325 participants, we also measured circulating folate, vitamin B12 and homocysteine. Pregnancy outcomes included preeclampsia (PE), gestational hypertension (GHT), small for gestational age (SGA), spontaneous preterm birth (sPTB) and gestational diabetes mellitus (GDM). Study findings show that maternal genotype MTHFR A1298C(CC) was associated with increased risk for PE, whereas TCN2 C766G(GG) had a reduced risk for sPTB. Paternal MTHFR A1298C(CC) and MTHFD1 G1958A(AA) genotypes were associated with reduced risk for sPTB, whereas MTHFR C677T(CT) genotype had an increased risk for GHT. FA supplementation was associated with higher serum folate and vitamin B12 concentrations, reduced uterine artery resistance index and increased birth weight. Women who supplemented with <800 µg daily FA at 15-week gestation had a higher incidence of PE (10.3%) compared with women who did not supplement (6.1%) or who supplemented with ≥800 µg (5.4%) (P < .0001). Higher serum folate levels were found in women who later developed GDM compared with women with uncomplicated pregnancies (Mean ± SD: 37.6 ± 8 nmol L-1 vs. 31.9 ± 11.2, P = .007). Fast food consumption was associated with increased risk for developing GDM, whereas low consumption of green leafy vegetables and fruit were independent risk factors for SGA and GDM and sPTB and SGA, respectively. In conclusion, maternal and paternal genotypes, together with maternal circulating folate and homocysteine concentrations, and pre- and early-pregnancy dietary factors, are independent risk factors for pregnancy complications.

The metabolic syndrome in pregnancy and its association with child telomere length.

AIMS/HYPOTHESIS: The aim of this study was to determine whether presence of the metabolic syndrome in pregnancy associates with child telomere length or child anthropometry (weight, BMI) and BP, measured at 10 years of age. METHODS: The Screening for Pregnancy Endpoints study (SCOPE) was a multicentre, international prospective cohort of nulliparous pregnant women recruited from Australia, New Zealand, Ireland and the UK (N = 5628). The current analysis is a 10 year follow-up of SCOPE pregnant women and their children, from the Australian cohort. Clinical data collected at 14-16 weeks' gestation during the SCOPE study were used to diagnose the metabolic syndrome using IDF criteria. Telomere length, a biomarker of ageing, was assessed by quantitative PCR from children's saliva collected at 10 years of age. RESULTS: In women who completed follow-up (n = 255), 20% had the metabolic syndrome in pregnancy. After adjusting for a range of confounders, children of mothers who had the metabolic syndrome in pregnancy had 14% shorter telomeres than children of mothers without the metabolic syndrome in pregnancy (mean difference -0.36 [95% CI -0.74, 0.01]). Height- and weight-for-age, and BMI z scores were similar in children of mothers who did and did not have the metabolic syndrome during pregnancy. CONCLUSIONS/INTERPRETATION: Children of mothers who had the metabolic syndrome in pregnancy have shorter telomeres, a biomarker of accelerated ageing. These findings warrant further studies in larger cohorts of children, as well as investigations into whether telomere length measured in cord blood associates with telomere length in childhood.

The deleterious effects of cannabis during pregnancy on neonatal outcomes.

OBJECTIVES: To evaluate whether cannabis use during pregnancy is associated with adverse neonatal outcomes that are independent of cigarette smoking. DESIGN: Prospective cohort study. SETTING: Adelaide (Australia), Auckland (New Zealand), Cork (Ireland), and Leeds, London and Manchester (United Kingdom). PARTICIPANTS: 5610 pregnant nulliparous women with low risk pregnancies recruited for the Screening for Pregnancy Endpoints (SCOPE) study, November 2004 - February 2011. At 14-16 weeks of pregnancy, women were grouped by self-reported cannabis use. MAIN OUTCOME MEASURES: Infant birthweight, head circumference, birth length, gestational age, and severe neonatal morbidity or mortality. RESULTS: 314 women (5.6%) reported using cannabis in the 3 months before or during their pregnancy; 97 (31%) stopped using it before and 157 (50%) during the first 15 weeks of pregnancy, while 60 (19%) were still using cannabis at 15 weeks. Compared with babies of mother who had never used cannabis, infants of those who still used it at 15 weeks had lower mean values for birthweight (adjusted mean difference [aMD], -127 g; 95% CI, -238 to -17 g), head circumference (aMD, -0.5 cm; 95% CI, -0.8 to -0.1 cm), birth length (aMD, -0.8 cm; 95% CI, -1.4 to -0.2 cm), and gestational age at birth (aMD, -8.1 days; 95% CI, -12.1 to -4.0 days). The differences for all outcomes except gestational age were greater for women who used cannabis more than once a week than for those who used it less frequently. CONCLUSIONS: Continuing to use cannabis during pregnancy is an independent risk factor for poorer neonatal outcomes.

Do raised two-hour pre-pregnancy insulin levels confer the same risks of developing GDM, as raised fasting levels, in recurrent miscarriage patients?

This study questioned whether raised pre-pregnancy two-hour (2 h) insulin levels, measured in recurrent embryonic miscarriage (RM) patients via a 75 g Oral Glucose Tolerance Test (OGTT), are associated with an increased risk of gestational diabetes mellitus (GDM) in a subsequent pregnancy. Patients had a 75 g OGTT and insulin levels evaluated (n = 170). 54.1% had normal glucose and insulin levels, 45.9% had levels indicating hyperinsulinism (HI). In the 98 patients who achieved a pregnancy, the prevalence of GDM was 3.7% in those without HI, and 35.7% in the patients who only had raised 2 h insulin levels. While HI has been described as a risk factor for miscarriages only in relation to raised fasting (basal) insulin levels, this study demonstrated that raised 2 h insulin levels predict an increased risk of GDM in a subsequent pregnancy. Thus raised 2 h insulin levels likely confer a similar risk to raised fasting insulin levels in RM patients.Impact statementWhat is already known on this subject? Fasting hyperinsulinism is known to be associated with an increased risk of gestational diabetes mellitus (GDM) in pregnancy. Hyperinsulinism, as reflected by the fasting (basal) insulin levels >20mU/L, has been recognized as a risk factor for recurrent miscarriages, particularly in patients with polycystic ovarian syndrome (PCOS), in the World literature. Raised two-hour insulin levels have not been considered as a risk factor in the literature before.What do the results of the study add? We have demonstrated a 10-fold increase in the development of GDM in patients with fasting insulin resistance, and/or raised 2h insulin levels, and an almost 10-fold increase in patients with only raised 2h levels. 58.8% of the patients who subsequently developed GDM only had raised 2h levels and would have been missed with routine testing.What are the implications of these findings for clinical practice and/or further research? Our study has demonstrated that GDM was three times more prevalent in the patients with only raised 2h levels, than in those only with raised fasting levels, reflecting insulin resistance/hyperinsulinism. Insulin studies including 2h insulin levels are therefore an important factor to consider when working up these patients. Insulin studies pre-pregnancy may be useful in identifying women at risk of suffering miscarriages or of developing GDM in a subsequent pregnancy.

Lifestyle and pregnancy complications in polycystic ovary syndrome: The SCOPE cohort study.

OBJECTIVES: To investigate the risk of pregnancy complications in women with and without polycystic ovary syndrome after consideration of lifestyle factors. DESIGN: Prospective cohort. PATIENTS AND MEASUREMENTS: Participants (n = 5628) were apparently healthy nulliparous women with singleton pregnancies from the Screening for Pregnancy Endpoints study in New Zealand, Australia, United Kingdom and Ireland. Multivariable regression models were performed assessing the association of self-reported polycystic ovary syndrome status with pregnancy complications with consideration of lifestyle factors at the 15th week of gestation. RESULTS: Women with polycystic ovary syndrome (n = 354) were older, had a higher socio-economic index and body mass index and were less likely to consume alcohol and smoke but more likely to do vigorous exercise and take multivitamins. In univariable analysis, polycystic ovary syndrome was associated with increased risk of gestational diabetes (OR: 2.2, 95% CI: 1.2, 4.0). In multivariable models, polycystic ovary syndrome was only significantly associated with decreased risk of large for gestational age (OR: 0.62, 95% CI: 0.40, 0.98) with a population attributable risk of 0.22%. None of the other outcomes were attributable to polycystic ovary syndrome status. CONCLUSIONS: Polycystic ovary syndrome is associated with a lower risk of large for gestational age infants. In this low-risk population, the risk of pregnancy complications was not increased in women with polycystic ovary syndrome who were following a healthy lifestyle. Further studies are warranted assessing the contribution of lifestyle factors to the risk of pregnancy complications in higher risk groups of women with and without polycystic ovary syndrome.

Low Serum Levels of HtrA3 at 15 Weeks of Gestation Are Associated with Late-Onset Preeclampsia Development and Small for Gestational Age Birth.

OBJECTIVE: The aim of this study was to investigate the potential utility of serum HtrA1 and HtrA3, serine proteases that are highly expressed in the developing placenta, at 15 and 20 weeks of gestation for predicting later development of adverse pregnancy outcomes of preeclampsia (PE), gestational hypertension (GHT), preterm birth (PTB), and small for gestational age (SGA) birth. METHODS: This is a nested case control study of 665 samples (330 controls, 335 cases) from the Adelaide SCOPE cohort. The cases included were 92 PE, 71 GHT, 56 PTB, and 116 SGA. Samples were assessed by ELISA and data adjusted for maternal age, BMI, socioeconomic index, hCG, and smoking status. Multivariate logistic regression was performed with other biochemical and biophysical parameters available for these samples. RESULTS: HtrA1 did not differ between the controls and cases. In contrast, HtrA3 was significantly lower at 15 weeks in pregnancies that later developed late-onset PE (LPE) or resulted in SGA birth, with an area under the ROC curve (AUC) of 0.716 and 0.790, respectively. The combination of HtrA3 with PAPP-A, uterine, and umbilical Doppler improved the AUC to 0.755 for LPE and 0.844 for SGA. CONCLUSION: HtrA3 at 15 weeks is associated with, and may be useful for, the early detection of LPE development and SGA birth.

Anti-Müllerian hormone levels in recurrent embryonic miscarriage patients are frequently abnormal, and may affect pregnancy outcomes.

This prospective cohort study measured anti-Müllerian hormone (AMH) levels in recurrent miscarriage (RM) patients, compared them to a normal population, and assessed the pregnancy outcomes. The RM patients demonstrated AMH levels that were significantly lower than the normal population, both in women aged ≤35 years, and those aged >35 years. AMH percentiles were found to be significantly lower in the study group of RM patients ≤35 years (p< .004) in the 5th and 50th percentiles, and in all percentiles in women >35 years (p< .03), were compared to women from a normal population. Serum AMH levels may reflect quality, and quantity of the remaining oocytes in these patients, and RM patients may have a low ovarian reserve, and a potentially poor oocyte quality, as shown by low circulating AMH. The evaluation of AMH levels in a RM work up may allow realistic counselling and possible ART referral in RM patients. Impact statement What is already known on this subject? There is some evidence to show that low AMH levels are associated with recurrent miscarriages and this is thought to be due to a decreased oocyte quality. The AMH levels are lower in the patients with endometriosis, and are often significantly higher in the patients with polycystic ovarian syndrome. Both conditions are independently associated with miscarriages. What the results of this study add? Anti-Müllerian hormone (AMH) levels were found to be significantly lower in recurrent miscarriage patients, compared to a normal population. This may be another factor contributing to miscarriages. The spontaneous pregnancy rates in the miscarriage group significantly improved with increasing AMH levels. This may confirm that patients with low AMH levels have poorer quality oocytes, and thus may be considered 'sub-fertile'. It was also found that the utilisation of assisted reproductive technologies (ART) to achieve a pregnancy was significantly reduced in the groups with a higher serum AMH. What the implications are of these findings for clinical practice and/or further research? Serum AMH levels should be offered to all patients as part of a recurrent miscarriage work up. Detecting the low AMH levels and counselling the patients on these findings may allow them the option of accessing ART. ART may have the ability to expedite conception rates, and with pre-implantation genetic analyses, could possibly select the embryos with the greatest chance of survival. Further research is needed to establish how the decreased AMH levels contribute to recurrent miscarriages.

Metabolic syndrome in pregnancy and risk for adverse pregnancy outcomes: A prospective cohort of nulliparous women.

BACKGROUND: Obesity increases the risk for developing gestational diabetes mellitus (GDM) and preeclampsia (PE), which both associate with increased risk for type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) in women in later life. In the general population, metabolic syndrome (MetS) associates with T2DM and CVD. The impact of maternal MetS on pregnancy outcomes, in nulliparous pregnant women, has not been investigated. METHODS AND FINDINGS: Low-risk, nulliparous women were recruited to the multi-centre, international prospective Screening for Pregnancy Endpoints (SCOPE) cohort between 11 November 2004 and 28 February 2011. Women were assessed for a range of demographic, lifestyle, and metabolic health variables at 15 ± 1 weeks' gestation. MetS was defined according to International Diabetes Federation (IDF) criteria for adults: waist circumference ≥80 cm, along with any 2 of the following: raised trigycerides (≥1.70 mmol/l [≥150 mg/dl]), reduced high-density lipoprotein cholesterol (<1.29 mmol/l [<50 mg/dl]), raised blood pressure (BP) (i.e., systolic BP ≥130 mm Hg or diastolic BP ≥85 mm Hg), or raised plasma glucose (≥5.6 mmol/l). Log-binomial regression analyses were used to examine the risk for each pregnancy outcome (GDM, PE, large for gestational age [LGA], small for gestational age [SGA], and spontaneous preterm birth [sPTB]) with each of the 5 individual components for MetS and as a composite measure (i.e., MetS, as defined by the IDF). The relative risks, adjusted for maternal BMI, age, study centre, ethnicity, socioeconomic index, physical activity, smoking status, depression status, and fetal sex, are reported. A total of 5,530 women were included, and 12.3% (n = 684) had MetS. Women with MetS were at an increased risk for PE by a factor of 1.63 (95% CI 1.23 to 2.15) and for GDM by 3.71 (95% CI 2.42 to 5.67). In absolute terms, for PE, women with MetS had an adjusted excess risk of 2.52% (95% CI 1.51% to 4.11%) and, for GDM, had an adjusted excess risk of 8.66% (95% CI 5.38% to 13.94%). Diagnosis of MetS was not associated with increased risk for LGA, SGA, or sPTB. Increasing BMI in combination with MetS increased the estimated probability for GDM and decreased the probability of an uncomplicated pregnancy. Limitations of this study are that there are several different definitions for MetS in the adult population, and as there are none for pregnancy, we cannot be sure that the IDF criteria are the most appropriate definition for pregnancy. Furthermore, MetS was assessed in the first trimester and may not reflect pre-pregnancy metabolic health status. CONCLUSIONS: We did not compare the impact of individual metabolic components with that of MetS as a composite, and therefore cannot conclude that MetS is better at identifying women at risk. However, more than half of the women who had MetS in early pregnancy developed a pregnancy complication compared with just over a third of women who did not have MetS. Furthermore, while increasing BMI increases the probability of GDM, the addition of MetS exacerbates this probability. Further studies are required to determine if individual MetS components act synergistically or independently.

Regulation of the human placental (pro)renin receptor-prorenin-angiotensin system by microRNAs.

STUDY QUESTION: Are any microRNAs (miRNAs) that target the placental renin-angiotensin system (RAS) in the human placenta suppressed in early gestation? SUMMARY ANSWER: Overall, 21 miRNAs with predicted RAS mRNA targets were less abundant in early versus term placentae and nine were more highly expressed. WHAT IS KNOWN ALREADY: Regulation of human placental RAS expression could alter placental development and therefore normal pregnancy outcome. The expression of genes encoding prorenin (REN), angiotensinogen, (pro)renin receptor, angiotensin converting enzyme 2, and the angiotensin II type 1 receptor are highest in early gestation, at a time when oxygen tension is at its lowest. Studies have shown that the human placental RAS is sensitive to oxygen, as are some miRNAs that regulate RAS mRNAs. We propose that in early pregnancy, the prevailing low O2 tension, by suppression of levels of miRNAs that target RAS mRNAs, results in increased expression of RAS mRNAs and encoded proteins. As gestation proceeds and the prevailing oxygen tension rises, abundance of these miRNAs increases, and placental RAS mRNA expression is suppressed. STUDY DESIGN, SIZE, DURATION: The expression of miRNAs was compared in human placentae collected in early (10-11 weeks; n = 7) and mid-gestation (14-18 weeks; n = 8) with placenta collected at term (38-40 weeks; n = 8). Expression of placental miRNAs in women with early (29-35.1 weeks; n = 8) or late-onset pre-eclampsia (PE) (>34-weeks gestation; n = 8) and gestational age matched preterm (31.6-35.1 weeks; n = 8) and term normotensive controls were also compared. PARTICIPANTS/MATERIALS, SETTING, METHODS: Agilent Human miRNA microarray v19 was used to detect up to 2006 miRNAs in four placentae from each group. Statistically different levels of expression were determined and refined using predictive modelling. Placental miRNAs predicted to target RAS mRNAs were identified in three databases. Differences detected on the array were confirmed for some miRNAs by semi-quantitative RT-PCR (qPCR, n = 7-8 for all groups). Two differentially expressed miRNAs that were known to target human renal REN mRNA (miR-181a-5p and miR-663) were transfected into human HTR-8/SVneo trophoblast cells to examine their effect on placental REN expression and prorenin levels. MAIN RESULTS AND THE ROLE OF CHANCE: In early gestation placentae, 186 miRNAs were differentially expressed compared with term placentae (109 increased, 77 decreased). Thirty of the differentially expressed miRNAs were predicted to target RAS components. In mid-gestation placentae, 117 miRNAs were differentially expressed compared with term placentae (69 increased, 48 decreased). Of these, 19 had RAS mRNAs as predicted targets. Eight miRNAs that were lower in early gestation and predicted to target RAS mRNAs were confirmed by qPCR. All showed an increase during gestation and could influence the transgestational profile of the human placental RAS. Additionally, on the array, three miRNAs predicted to target RAS mRNAs (miR-892c-3p, miR-378c and miR-514b-3p) were overexpressed in placentae from women with late-onset PE (P = 3.6E-10, P = 1.8E-05, P = 5.3E-06; respectively). miR-663, which suppresses renal REN mRNA expression, was overexpressed in early-onset PE placentae as determined by qRT-PCR analysis (P = 0.014). Transfection of miR-181a-5p and miR-663 into HTR-8/SVneo trophoblast cells suppressed REN mRNA expression (P = 0.05) and prorenin protein production (P = 0.001). LARGE SCALE DATA: Data can be found via GEO accession number GSE109832. LIMITATIONS, REASONS FOR CAUTION: Further validation that the differentially expressed miRNAs do indeed directly target RAS mRNAs and affect placental development and function is required. This study is limited by the small sample size. Therefore independent validation in a larger cohort is required. WIDER IMPLICATIONS OF THE FINDINGS: We propose that suppression of miRNAs that target the placental RAS in early gestation is partly responsible for the increase in RAS expression at this time, in order to promote placental development. Later in pregnancy, we have detected overexpression of several miRNAs in placentae from women with PE. These may prove to be biomarkers for early detection of women at risk of developing PE. Since the placenta produces at least two miRNAs that were found in the kidney to target REN mRNA, and that also target placental REN mRNA, the escape of these miRNAs into the maternal circulation in excess amounts could affect maternal renal REN mRNA production and thereby disturb maternal fluid and electrolyte homoeostasis. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Health and Medical Research Council, Australia (APP1043537). K.G.P. is supported by an Australian Research Council Future Fellowship (FT150100179). C.T.R. is supported by a Lloyd Cox Professorial Research Fellowship from the University of Adelaide. F.Z.M. is supported by a National Heart Foundation Future Leader Fellowship and Baker Heart and Diabetes Institute Fellowship. The authors declare that they have no competing interests.

Formyl peptide receptor-2 is decreased in foetal growth restriction and contributes to placental dysfunction.

STUDY QUESTION: What is the association between placental formyl peptide receptor 2 (FPR2) and trophoblast and endothelial functions in pregnancies affected by foetal growth restriction (FGR)? SUMMARY ANSWER: Reduced FPR2 placental expression in idiopathic FGR results in significantly altered trophoblast differentiation and endothelial function in vitro. WHAT IS KNOWN ALREADY: FGR is associated with placental insufficiency, where defective trophoblast and endothelial functions contribute to reduced feto-placental growth. STUDY DESIGN, SIZE, DURATION: The expression of FPR2 in placental tissues from human pregnancies complicated with FGR was compared to that in gestation-matched uncomplicated control pregnancies (n = 25 from each group). Fpr2 expression was also determined in placental tissues obtained from a murine model of FGR (n = 4). The functional role of FPR2 in primary trophoblasts and endothelial cells in vitro was assessed in diverse assays in a time-dependent manner. PARTICIPANTS/MATERIALS, SETTING, METHODS: Placentae from third-trimester pregnancies complicated by idiopathic FGR (n = 25) and those from gestation-matched pregnancies with appropriately grown infants as controls (n = 25) were collected at gestation 27-40 weeks. Placental tissues were also collected from a spontaneous CBA/CaH × DBA/2 J murine model of FGR. Placental FPR2/Fpr2 mRNA expression was determined by real-time PCR, while protein expression was examined by immunoblotting and immunohistochemistry. siRNA transfection was used to silence FPR2 expression in primary trophoblasts and in human umbilical vein endothelial cells (HUVEC), and the quantitation of cytokines, chemokines and apoptosis was performed following a cDNA array analyses. Functional effects of trophoblast differentiation were measured using HCGB/ß-hCG and syncytin-2 expression as well as markers of apoptosis, tumour protein 53 (TP53), caspase 8, B cell lymphoma 2 (BCL2) and BCL associated X (BAX). Endothelial function was assessed by proliferation, network formation and permeability assays. MAIN RESULTS AND THE ROLE OF CHANCE: Placental FPR2/Fpr2 expression was significantly decreased in FGR placentae (n = 25, P < 0.05) as well as in murine FGR placentae compared to controls (n = 4, P < 0.05). FPR2 siRNA (siFPR2) in term trophoblasts significantly increased differentiation markers, HCGB and syncytin-2; cytokines, interleukin (IL)-6, CXCL8; and apoptotic markers, TP53, caspase 8 and BAX, but significantly reduced the expression of the chemokines CXCL12 and its receptors CXCR4 and CXCR7; CXCL16 and its receptor, CXCR6; and cytokine, IL-10, compared with control siRNA (siCONT). Treatment of HUVECs with siFPR2 significantly reduced proliferation and endothelial tube formation, but significantly increased permeability of HUVECs. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Reduced expression of placental FPR2/Fpr2 was observed in the third trimester at delivery after development of FGR, suggesting that FPR2 is associated with FGR pregnancies. However, there is a possibility that the decreased placental FPR2 observed in FGR may be a consequence rather than a cause of FGR, although our in vitro functional analyses using primary trophoblasts and endothelial cells suggest that FPR2 may have a direct or indirect regulatory role on trophoblast differentiation and endothelial function in FGR. WIDER IMPLICATIONS OF THE FINDINGS: This is the first study linking placental FPR2 expression with changes in the trophoblast and endothelial functions that may explain the placental insufficiency observed in FGR. STUDY FUNDING/COMPETING INTERESTS: P.M. and P.R.E. received funding from the Australian Institute of Musculoskeletal Science, Western Health, St. Albans, Victoria 3021, Australia. M.L. is supported by a Career Development Fellowship from the National Health and Medical Research Council (NHMRC; Grant no. 1047025). Monash Health is supported by the Victorian Government's Operational Infrastructure Support Programme. The authors declare that there is no conflict of interest in publishing this work.

Improving pregnancy outcomes in humans through studies in sheep.

Experimental studies that are relevant to human pregnancy rely on the selection of appropriate animal models as an important element in experimental design. Consideration of the strengths and weaknesses of any animal model of human disease is fundamental to effective and meaningful translation of preclinical research. Studies in sheep have made significant contributions to our understanding of the normal and abnormal development of the fetus. As a model of human pregnancy, studies in sheep have enabled scientists and clinicians to answer questions about the etiology and treatment of poor maternal, placental, and fetal health and to provide an evidence base for translation of interventions to the clinic. The aim of this review is to highlight the advances in perinatal human medicine that have been achieved following translation of research using the pregnant sheep and fetus.