Maternal Continuing Folic Acid Supplementation after the First Trimester of Pregnancy Increased the Risk of Large-for-Gestational-Age Birth: A Population-Based Birth Cohort Study.

Supplementation with folic acid (FA) was proven to prevent neural tube defects (NTDs) and was recommended worldwide before and during early pregnancy. However, much less is known regarding the role of FA after the 12th gestational week (GW). This study aimed to investigate the related effects of continued FA supplementation after the first trimester of pregnancy on fetal growth. The study subjects came from the Ma'anshan-Anhui Birth Cohort Study (MABC) that recruited 3474 pregnant women from the city of Ma'anshan in Anhui Province in China during the period of May 2013 to September 2014. The information on use of vitamin and mineral supplements was recorded in different periods (the first/second/third trimester of pregnancy). Small-for-gestational-age (SGA) births were live-born infants that were <10th percentile of birth weight, and large-for-gestational-age (LGA) births were live-born infants that were ≥90th percentile of birth weight according to nomograms based on gender and gestational age from the latest standards. We used multivariable logistic regression to evaluate the effects of FA supplement consumption in the second/third trimester of pregnancy on the risk of LGA and SGA. In addition, propensity score analysis was also performed to examine the effects. In this prospective birth cohort study conducted in Chinese women who had taken FA in the first trimester of pregnancy, we found that continued FA supplementation with 400 micrograms/day in the second and third trimesters of pregnancy significantly increased the risk of LGA (RR = 1.98 (1.29, 3.04)). This relation was strong or monotonic after adjusting for maternal age, newborn's gender, maternal pre-pregnancy BMI, maternal education level, smoking, alcohol consumption and calcium supplementation. We did not observe that continuing FA supplementation after the first trimester of pregnancy remarkably decreased the risk of SGA. The propensity score analysis showed similar results. To confirm these findings, additional investigations or trials with a large sample and the tracking of folate status throughout pregnancy are recommended.

[Prepregnancy body mass index, gestational weight gain and hypertensive disorder complicating pregnancy: a prospective cohort study in Ma'anshan City].

OBJECTIVE: To evaluate the associations between pregnancy body mass index (B MI), gestational weight gain (GWG) and the risk for hypertensive disorder complicating pregnancy (HDCP). Methods In this prospective cohort study, subjects who had their first prenatal examination (gestational age ≤ 14 weeks) at Ma'anshan Maternal and Child Health Care Center were recruited under informed consent, from May 16, 2013 to September 11, 2014. All the information were collected through questionnaires, height, weight and maternal blood pressure were measured, and urine protein was detected in the first, second, and third trimester of pregnancy. RESULTS: The incidence of HDCP was 6.09% (196/3219), and preeclampsia was 1.77% (57/3219). After adjusting confounding factors, results in Logistic regression analysis showed that prepregnancy overweight and obesity, weight gain more than recommended during pregnancy were the risk factor of HDCP, the adjusted odds ratios (95% CI) were 2.33 (1.56 - 3.47), 7.85 (4.65 - 13.24) and 1.86 (1.24 - 2.79), respectively. CONCLUSION: Prepregnancy overweight, obeisity, weight gain more than recommended during pregnancy were associated with increased risk of HDCP.

Maternal Snoring May Predict Adverse Pregnancy Outcomes: A Cohort Study in China.

OBJECTIVE: To examine the prevalence of snoring during pregnancy and its effects on key pregnancy outcomes. METHODS: Pregnant women were consecutively recruited in their first trimester. Habitual snoring was screened by using a questionnaire in the 1st and 3rd trimester, respectively. According to the time of snoring, participants were divided into pregnancy onset snorers, chronic snorers and non-snorers. Logistic regressions were performed to examine the associations between snoring and pregnancy outcomes. RESULTS: Of 3 079 pregnant women, 16.6% were habitual snorers, with 11.7% were pregnancy onset snorers and 4.9% were chronic snorers. After adjusting for potential confounders, chronic snorers were independently associated with gestational diabetes mellitus (GDM) (RR 1.66, 95%CI 1.09-2.53). Both pregnancy onset and chronic snorers were independently associated with placental adhesion (RR 1.96, 95%CI 1.17-3.27, and RR 2.33, 95%CI 1.22-4.46, respectively). Pregnancy onset snorers were at higher risk of caesarean delivery (RR 1.37, 95%CI 1.09-1.73) and having macrosomia (RR 1.54, 95%CI 1.05-2.27) and large for gestational age (LGA) (RR 1.71, 95%CI 1.31-2.24) infants. In addition, being overweight or obese before pregnancy plays an important role in mediating snoring and adverse pregnancy outcomes. CONCLUSIONS: Maternal snoring may increase the risk of adverse pregnancy outcomes, and being overweight or obese before pregnancy with snoring is remarkable for researchers. Further studies are still needed to confirm our results.

[Mid-gestational glucose levels and newborn birth weight: birth cohort study].

OBJECTIVE: To understand the association between the blood glucose levels of pregnant women in second trimester detected by 75 gram oral glucose tolerance test (OGTT) and the birth weight of neonates. METHODS: Demographic information collection and OGTT were conducted for 3 081 pregnant women at ≤14 gestational weeks and 24-28 gestational weeks respectively. Multiple logistic regression analysis was done to identify the factors associated with the birth weight and the risks of large for gestational age (LGA) in three levels (FPG, OGTT-1 h and OGTT-2 h) of OGTT percentile group, multiple linear regression analysis was used to evaluate the relationships between maternal glucose levels and neonate birth weight. RESULTS: Pre-pregnancy obesity (24.0 kg/m2≤BMI<28.0 kg/m2) (OR=1.4, 95%CI:1.0-2.0, P=0.029) and gestational diabetes mellitus (OR=2.4,95% CI: 1.8-3.2, P<0.001) were the risk factors. Pre-pregnancy underweight (BMI<18.5 kg/m2) (OR=1.6, 95%CI: 1.2-2.2, P=0.003), preeclampsia (OR=4.0, 95%CI: 1.9-8.4, P<0.001) increased the risk for small for gestational age (SGA). Multiple linear regression analysis showed neonate birth weight was positive correlated with maternal glucose levels (ß were 91.99, 33.60, 32.00, respectively, P<0.001). Percentile groups of each OGTT level was linearly positive associated with increased mean value of neonate birth weight, and so with the risk of LGA. CONCLUSIONS: There were positive correlations between maternal glucose levels and neonate birth weight. The risk of LGA increased with the maternal glucose levels, but there was no statistical association between SGA and maternal glucose levels. FPG level is one of the predictors of LGA. Active surveillance and control of maternal glucose level can effectively reduce the risk of LGA.