Association of prenatal exposures of parabens with children’s obesity－A longitudinal cohort study

Abstract

BACKGROUND AND AIM: The association between prenatal exposure of parabens and children’s obesity was inconclusive and we aimed to exam it. METHODS: Mother-newborn pairs were enrolled at the 3rd trimester during pregnancy and followed as children aged 2-3, 5-6, 8-9, 11-12, 14-15, and 17-18 years in central Taiwan. Information were collected via questionnaires, physical examinations, and bio-samples. Urinary concentrations of methyl paraben (MP), ethyl paraben (EP), propyl paraben (PP), butyl paraben (BP) in pregnant women and 17-18 years-old children were determined using liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) and corrected by urinary creatinine level. Molar concentrations of the four parabens were summed to ΣPB. Children’s body mass index (BMI) were calculated at each follow-up. Ordinary linear regression model was performed. RESULTS:Prenatal exposure levels of MP, EP, PP, BP, and ΣPB were similar in 92 male and 99 female children. MP was with the highest and EP was with the lowest concentration. After adjustment for child sex, annual family income, parental education level, maternal BMI, and weight gain, the associations of children’s BMI with prenatal exposure of MP and ΣPB were positive though non-significant at ages of 2-3 years and null at ages of 5-6 years. The associations turned to be negative since ages of 8-9 years and borderline significant at ages of 14-15 years. In analyses at ages of 17-18 years, we additionally adjusted for children’s paraben exposure levels and found that per log10 μg/g MP and ΣPB increase in-utero were significantly associated with 1.20 and 1.32 reductions of BMI (p=0.022 and 0.017). CONCLUSIONS:MP was the most common paraben the pregnant women exposed in central Taiwan. The association between prenatal exposure of parabens and children’s BMI may vary with age, it tended to be positive in toddlers and negative from puberty to post-puberty. KEYWORDS: Obesity and metabolic disorders, Children's environmental health, Endocrine disrupting chemicals, Environmental epidemiology, Food/nutrition, Birth outcomes