Associations of Prenatal Paraben Exposure with Markers of Fetal Growth

Abstract

PDS 74: Pregnancy outcomes, Exhibition Hall (PDS), Ground floor, August 26, 2019, 1:30 PM - 3:00 PM Background/Aim: Parabens, endocrine disrupting chemicals in personal care and consumer products, are detected in most pregnant women. Associations of parabens with birth outcomes have been inconsistent; thus we investigated associations between gestational paraben concentrations and birth outcomes. Methods: In 294 predominantly Caucasian, college-educated Illinois women, butylparaben, ethylparaben, methylparaben, and propylparaben concentrations were quantified in cross-pregnancy pools of five first-morning urine samples. Covariate-adjusted generalized linear models assessed associations between natural log (ln)-parabens and gestational age at birth (GA, weeks), birthweight (BW, g), and birth length (BL, cm). Mediation analyses assessed whether GA mediated associations of parabens with birth size. Interactions of parabens with infant sex were explored. Results: Paraben concentrations were similar to reported concentrations in U.S. women. Butylparaben was not associated with birth outcomes. Associations with other parabens were only observed in female newborns. Only methylparaben (which had the highest concentrations) was negatively associated with GA. Specifically, each ng/mL increase in ln-methylparaben was associated with 0.1 weeks shorter gestation in newborn girls (95%CI: -0.3, 0.004). Furthermore, maternal urinary methylparaben was negatively associated with birth size in girls. Each ng/mL increase in ln-methylparaben was associated with 81.3g smaller BW (95%CI: -134.1, -28.4), and 24.1% (β: -19.6g; 95%CI: -40.2, 1.0) of this association was attributable to the association of methylparaben with GA. Similarly, each ng/mL increase in ln-methylparaben was associated with 0.3cm shorter BL (95%CI: -0.6, -0.1), and 28.3% (β: -0.1cm; 95%CI: -0.2, 0.01) of this association was due to the association of methylparaben with GA. Associations of ethylparaben and propylparaben with BW and BL were significant, but with smaller effect estimates than methylparaben. Conclusions: Methylparaben, ethylparaben, and propylparaben maternal concentrations were negatively associated with fetal growth in newborn girls. Methylparaben additionally decreased gestation duration, which partially mediated associations of methylparaben with birth size. These findings should be corroborated in other populations.