Maternal levels of perfluorinated chemicals and subfecundity

TLDR

Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are ubiquitous man‑made compounds that may act as hormonal disruptors. The study examined whether maternal exposure to PFOA and PFOS during pregnancy decreases human fecundity. Researchers measured plasma PFOS and PFOA levels in 1,240 Danish pregnant women, recorded time‑to‑pregnancy categories, defined infertility as TTP > 12 months or treatment, and estimated fecundity odds ratios using Cox discrete‑time models. Higher maternal PFOS and PFOA concentrations were linked to longer time‑to‑pregnancy and increased infertility odds, with significant dose‑response trends suggesting that typical exposure levels may reduce fecundity.

Abstract

Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are ubiquitous man-made compounds that are possible hormonal disruptors. We examined whether exposure to these compounds may decrease fecundity in humans.Plasma levels of PFOS and PFOA were measured at weeks 4-14 of pregnancy among 1240 women from the Danish National Birth Cohort recruited from 1996 to 2002. For this pregnancy, women reported time to pregnancy (TTP) in five categories (<1, 1-2, 3-5, 6-12 and >12 months). Infertility was defined as having a TTP of >12 months or received infertility treatment to establish this pregnancy.Longer TTP was associated with higher maternal levels of PFOA and PFOS (P < 0.001). Compared with women in the lowest exposure quartile, the adjusted odds of infertility increased by 70-134 and 60-154% among women in the higher three quartiles of PFOS and PFOA, respectively. Fecundity odds ratios (FORs) were also estimated using Cox discrete-time models. The adjusted FORs were virtually identical for women in the three highest exposure groups of PFOS (FOR = 0.70, 0.67 and 0.74, respectively) compared with the lowest quartile. A linear-like trend was observed for PFOA (FOR = 0.72, 0.73 and 0.60 for three highest quartiles versus lowest quartile). When all quartiles were included in a likelihood ratio test, the trends were significant for PFOS and PFOA (P = 0.002 and P < 0.001, respectively).These findings suggest that PFOA and PFOS exposure at plasma levels seen in the general population may reduce fecundity; such exposure levels are common in developed countries.