In an article published on March 30, 2018 in the peer-reviewed journal Environment International, Eva Govarts from the Unit Environmental Risk and Health, Flemish Institute for Technological Research (VITO), Belgium, together with colleagues from several other European institutes, reported on the results of a large European study analyzing associations between prenatal exposure to endocrine disrupting chemicals (EDCs) and the risk of babies being born with the adverse condition “small for gestational age” (SGA). SGA weight is defined as birth weight that is below the 10th percentile for the accepted norms, which differ slightly depending on the baby’s sex or country of birth.
The scientists measured the concentrations of several presumed EDCs in maternal blood, cord blood, and breast milk samples obtained from mother-child pairs registered in seven European birth cohorts studied between 1997 and 2012. They then used logistic regression analysis to model the associations between EDC concentrations and SGA. Additional factors explored were children’s sex and mothers’ smoking during pregnancy.
Roughly 10% of babies across all the analyzed cohorts were SGA. Two per- and polyfluoroalkyl substances (PFASs), namely perfluorooctane sulfonate (PFOS, CAS 1763-23-1) and perfluorooctanoic acid (PFOA, CAS 335-67-1), were evaluated in the set of 693 mother-child pairs. Higher levels of PFOA were found to be associated with greater risk of SGA. For PFOS, the observed associations depended on the smoking status of the mother. Namely, a direct association between elevated PFOS and increased SGA risk was observed among the babies born to mothers who smoked during pregnancy, while an inverse association was found for the babies of non-smoking mothers.
The authors conclude that “prenatal environmental exposure to . . . perfluorinated compounds with endocrine disrupting properties may contribute to the prevalence of SGA.” Since the direction of the observed associations depends on maternal smoking status, “diverse mechanisms of action and biological pathways” could be involved.
Govarts, E., et al. (2018). “Prenatal exposure to endocrine disrupting chemicals and risk of being born small for gestational age: Pooled analysis of seven European birth cohorts.” Environment International 115:267-278.