Maternal urinary paraben levels and offspring size at birth from a Chinese birth cohort

Background Parabens are suspected to impair fetal growth because of their endocrine disrupting effects. Epidemiological studies regarding the effects of prenatal exposure to parabens on birth outcomes are limited. Objectives Our aim was to evaluate the association between prenatal paraben exposure and size of infants at birth. Methods Within the longitudinal Healthy Baby Cohort (HBC) in Hubei Province, China, we randomly selected 1006 mother-infant pairs recruited in Wuhan City in 2014. Concentrations of parabens were measured in maternal urine collected before delivery. General linear models were used to analyze the associations of maternal parabens exposure levels with birth weight and birth length. Results The specific gravity adjusted geometric means for urinary concentrations of methyl paraben (MeP), ethyl paraben (EtP), and propyl paraben (PrP) were 5.41, 0.11, and 0.94 ng/mL, respectively. Maternal urinary concentrations of parabens tended to be positively associated with birth weight in boys, while opposite trends were found in girls, though these associations were not significant. Higher maternal urinary levels of MeP were positively associated with birth length in boys (β = 0.30, 95% CI: 0.01, 0.58 for the medium tertile, and β = 0.30, 95% CI: 0.01, 0.58 for the highest tertile compared to the lowest tertile); however, no significant associations with birth length were observed in girls. Conclusions Maternal urinary levels of MeP were positively associated with length at birth in boys. Besides, we did not find strong associations of the current exposure levels of parabens in Chinese pregnant women with size of infants at birth.