Organophosphate flame retardants (OPFRs), used as flame retardants and plasticizers, have been suggested to impair fetal growth and development in toxicological studies, but epidemiological data are extremely limited. This study was designed to explore whether prenatal exposure to OPFRs was associated with an increased risk of low birth weight (LBW) using a nested case-control design based on the ongoing prospective birth cohort in Wuhan, China. A total of 113 cases and 226 matched controls recruited from this cohort project in 2014−2016 were included. OPFR metabolite concentrations in maternal urine samples collected in the third trimester were determined, and birth outcomes were extracted from medical records. Compared with the lowest tertile of diphenyl phosphate (DPHP) concentrations, pregnant women with the highest tertile of DPHP had a 4.62-fold (95% confidence interval (CI): 1.72, 12.40) significantly increased risk for giving birth to LBW infants, with a significant dose−response relationship (p-trend < 0.01). After stratification by newborn sex, the significant positive association of DPHP levels with LBW risk was merely observed among female newborns. Our results suggest a positive association between maternal urinary DPHP concentrations and LBW risk for the first time, and the effect appears be sex-specific.

No abstract

BackgroundHypertensive disorders of pregnancy (HDP) are major causes of maternal death worldwide and the risk factors are not fully understood. Few studies have investigated the risk factors for HDP among Chinese women. A cohort study involving 84,656 women was conducted to investigate pre-pregnancy BMI, total gestational weight gain (GWG), and GWG during early pregnancy as risk factors for HDP among Chinese women.MethodsThe study was conducted between 2011–2013 in Wuhan, China, utilizing data from the Maternal and Children Healthcare Information Tracking System of Wuhan. A total of 84,656 women with a live singleton pregnancy were included. Multiple unconditional logistic regression was conducted to evaluate associations between putative risk factors and HDP.ResultsWomen who were overweight or obese before pregnancy had an elevated risk of developing HDP (overweight: OR = 2.66, 95% CI = 2.32–3.05; obese: OR = 5.53, 95% CI = 4.28–7.13) compared to their normal weight counterparts. Women with total GWG above the Institute of Medicine (IOM) recommendation had an adjusted OR of 1.72 (95% CI = 1.54–1.93) for HDP compared to women who had GWG within the IOM recommendation. Women with gestational BMI gain >10 kg/m2 during pregnancy had an adjusted OR of 3.35 (95% CI = 2.89–3.89) for HDP, compared to women with a gestational BMI gain <5 kg/m2. The increased risk of HDP was also observed among women with higher early pregnancy (up to 18 weeks of pregnancy) GWG (>600g/wk: adjusted OR = 1.48, 95% CI = 1.19–1.84).ConclusionThe results from this study show that maternal pre-pregnancy BMI, early GWG, and total GWG are positively associated with the risk of HDP. Weight control efforts before and during pregnancy may help to reduce the risk of HDP.

No abstract

No abstract

Rationale: In 2017, the American College of Cardiology (ACC)/American Heart Association (AHA) released a new hypertension guideline for nonpregnant adults, using lower blood pressure values to identify hypertension. However, the impact of this new guideline on the diagnosis of gestational hypertension and the associated maternal and neonatal risks are unknown. Objective: To estimate the impact of adopting the 2017 ACC/AHA guideline on detecting gestational blood pressure elevations and the relationship with maternal and neonatal risk in the perinatal period using a retrospective cohort design. Methods and Results: This study included 16 345 women from China. Systolic and diastolic blood pressures of each woman were measured at up to 22 prenatal care visits across different stages of pregnancy. Logistic and linear regressions were used to estimate associations of blood pressure categories with the risk of preterm delivery, early-term delivery, and small for gestational age, and indicators of maternal liver, renal, and coagulation functions during pregnancy. We identified 4100 (25.1%) women with gestational hypertension using the 2017 ACC/AHA guideline, compared with 4.2% using the former definition. Gestational hypertension, but not elevated blood pressure (subclinical blood pressure elevation), was significantly associated with altered indicators of liver, renal, and coagulation functions during pregnancy for mothers and increased risk of adverse birth outcomes for newborns; adjusted odds ratios (95% CIs) for gestational hypertension stage 2 were 2.23 (1.18–4.24) for preterm delivery, 2.05 (1.67–2.53) for early-term delivery, and 1.43 (1.13–1.81) for small for gestational age. Conclusions: Adopting the 2017 ACC/AHA guideline would result in a substantial increase in the prevalence of gestational hypertension; subclinical blood pressure elevations during late pregnancy were not associated with increased maternal and neonatal risk in this cohort. Therefore, the 2017 ACC/AHA guideline may improve the detection of high blood pressure during pregnancy and the efforts to reduce maternal and neonatal risk. Replications in other populations are required.

No abstract

Parental pre-pregnancy overweight/obesity and excessive GWG during pregnancy were highly associated with macrosomia. The association with GWG was most pronounced in mothers who had a normal or underweight pre-pregnancy BMI. Weight control efforts before pregnancy for mothers and fathers as well as control of maternal gain during pregnancy may reduce the risk of macrosomia.