Age at Menarche, Menstrual Characteristics, and Risk of Preeclampsia

We examined associations of age at menarche and menstrual characteristics with the risk of preeclampsia among participants (n = 3,365) of a pregnancy cohort study. Data were collected using in-person interviews and medical record abstraction. Logistic regression was used to estimate adjusted odds ratio (OR) and 95% confidence interval (95% CI). There was a significant inverse association between age at menarche and risk of preeclampsia (P value for trend < 0.05). Association of long cycle length (>36 days) with higher risk of preeclampsia was present only among women who had prepregnancy body mass index <25 kg/m2 (interaction P value = 0.04). Early menarche is associated with higher risk of preeclampsia. Prepregnancy weight may modify associations of long menstrual cycles with risk of preeclampsia

Placental genetic variations in vitamin D metabolism and birthweight.

INTRODUCTION: Vitamin D has pleiotropic functions that regulate fetal growth and development. We investigated associations of common placental genetic variations in vitamin D metabolism with birthweight. METHODS: The study was conducted among participants (506 maternal-infant pairs) of a pregnancy cohort study. Data were collected using interviewer-administered questionnaires and post-delivery medical record abstraction. DNA, extracted from placental samples collected at delivery, was genotyped for eight single nucleotide polymorphisms (SNPs) in five vitamin D metabolism genes (CUBN, LRP2, VDR, GC, and CYP2R1). Linear and logistic regression models were used to evaluate associations of SNPs with birthweight and risk of low birthweight, respectively. Effect modification of associations by infant sex was examined using stratified analyses and interaction terms in regression models. RESULTS: Mean (standard-deviation) birthweight among all, male, and female infants was 3482.1 (549.9), 3544.6 (579.0) and 3419.2 (512.5) grams, respectively. Each copy of the minor allele of rs2282679 (GC) was associated with a 68.6 g (95%CI:3.1134.7 g) increase in birthweight overall. Sex-specific associations were observed for SNP rs4667591 (LRP2) (p-value for interaction \u3c 0.001). Each copy of the minor allele of rs4667591 was associated with a 124.7 g (95%CI:20.1229.0 g) increase in birthweight among female infants, and a suggested 81.6 g decrease in birthweight among male infants (95%CI:-183.7,20.5 g). DISCUSSION: Our study identified overall and sex-specific associations between placental genetic variations in vitamin D metabolism and birthweight. If confirmed by larger replication studies, observed associations may provide insight into mechanistic underpinnings of the relationships between placental vitamin D metabolism and birth size

Early Pregnancy Maternal Hepatocyte Growth Factor and Risk of Gestational Diabetes

Aims We investigated associations of serum hepatocyte growth factor (HGF) with risk of gestational diabetes mellitus (GDM). We also examined whether pre-pregnancy overweight/obesity status or leisure-time physical activity (LTPA) modify these associations. Methods: In a nested case-control study (173 GDM cases and 187 controls) among participants of a pregnancy cohort, early pregnancy (16 weeks of gestation, on average) serum HGF was measured using enzyme-linked immunoassay. GDM was diagnosed using American Diabetes Association guidelines. Logistic regression was used to calculate odd ratios (ORs) and 95% confidence intervals (CI). Effect modifications by pre-pregnancy overweight/obesity status or LTPA during pregnancy were examined using stratified analyses and interaction terms. Results: Overall, we did not find significant associations of serum HGF with GDM risk (p-value> 0.05). However, compared with women who had low serum HGF concentrations (<2.29 ng/ml), women with high serum HGF concentrations (≥ 2.29 ng/ml) had 3.8-fold (95%CI: 1.30–10.98) and 4.5-fold (95%CI: 1.28–15.80) higher GDM risk among women who were overweight/obese, pre-pregnancy (body mass index≥25 kg/m2), or did not report LTPA, respectively. These associations were not present among women who were not overweight/obese (interaction p=0.05) or reported LTPA (interaction p=0.05). Conclusion: Overweight/obesity status and LTPA may modify associations of early pregnancy serum HGF with subsequent GDM risk