Prenatal exposures to phthalates and postnatal growth in boys during the three first years of life

摘要

Background: A recent study reported a relationship between urinary concentrations of monoethyl phthalate (MEP) and body size in a New York City population of overweight children. Aims: To study the association between maternal pregnancy exposure to phthalates and male offspring's postnatal growth in a prospective setting. Methods: In a subsample of 520 pregnant women from EDEN mother-child cohort who gave birth to a boy, we measured 11 phthalate metabolites in one spot maternal urine samples collected at 22-29 weeks of gestation. Using weight and height measured during the clinical exams or collected from health booklet (respectively, median=17 and 15 measures / child), we modeled individual growth trajectories from birth to 3 years and calculated weight and height growth velocities. The associations between metabolite concentrations and growth parameters were studied using adjusted linear models and reported for one inter-quartile range (IQR) increase in exposure biomarkers. Results: Concentrations of phthalate metabolites were not significantly associated with birthweight. An IQR increase in MEP and in monobenzyl phthalate (MBzP) were associated with increased weight at 30 months (respectively β=127g, p=0.07 and β=149 g, p=0.02). The associations emerged earlier for MBzP which was positively associated with weight growth velocity (WGV) at 3 months (β=16.1g/mo, p=0.002) than for MEP (strongest association with WGV at 2 years: β=5.8g/mo, p=0.007). We also found an inverse-U shape association between high-molecular weight phthalates and weight at 30 months. There was no significant association with height growth parameters. Discussion: We highlighted associations between exposure to butylbenzyl (metabolite=MBzP) and diethyl (metabolite=MEP) phthalates during pregnancy and postnatal body size in boys, with different timing of occurence. Results need to be replicated in other mother-child cohort studies with repeated exposure assessment.