Associations between urinary bisphenol A concentrations during pregnancy and gestational age

ObjectiveWe aimed to assess the association between urinary bisphenol A(BPA)concentrations and gestational age in pregnant women.

MethodsA total of 248 pregnant women were recruited from a maternal and child care hospital in Shanghai. A questionnaire survey was completed to collect socio-demographic information and spot urine samples were collected during pregnancy. Gas chromatography-tandem mass spectrometry(GC-MS/MS)was used to measure BPA concentrations in urine samples. Linear relationship between urinary BPA level and gestational age was assessed by using generalized additive models. Multivariate regression model was used to evaluate associations of prenatal BPA exposure with gestational age.

ResultsBPA was detected in all the urine samples. Median value and geometric mean of urinary BPA levels were 0.85 μg/L and 1.21 μg/L, respectively. Linear relationship between urinary BPA concentration and gestational weeks was confirmed(non-linear P > 0.05). Positive association between urinary BPA level and gestational age was indicated(regression coefficient, β = 0.19;95%CI:0.04-0.35;P = 0.016). However, it was only observed in girls, stratified by sex of newborns(β = 0.18;95%CI:0.03-0.34;P = 0.020). After stratification by trimester, no significant association was found in the second or the third trimesters.

ConclusionPregnant women are extensively exposed to BPA. Urinary BPA exposure during pregnancy may extend gestational age, especially in girls.