Associations between lifestyle factors and levels of per- and polyfluoroalkyl substances (PFASs), phthalates and parabens in follicular fluid in women undergoing fertility treatment

Background: Concerns have been raised whether exposure to endocrine-disrupting chemicals (EDCs) can alter reproductive functions and play a role in the aetiology of infertility in women. With increasing evidence of adverse effects, information on factors associated with exposure is necessary to form firm recommendations aiming at reducing exposure.Objective: Our aim was to identify associations between lifestyle factors including the home environment, use of personal care products (PCP), and dietary habits and concentrations of EDCs in ovarian follicular fluid.Methods: April-June 2016, 185 women undergoing ovum pick-up for in vitro fertilisation in Sweden were recruited. Correlation analyses were performed between self-reported lifestyle factors and concentration of EDCs analysed in follicular fluid. Habits related to cleaning, PCPs, and diet were assessed together with concentration of six per- and polyfluoroalkyl substances (PFASs) [PFHxS, PFOA, PFOS, PFNA, PFDA and PFUnDA], methyl paraben and eight phthalate metabolites [MECPP, MEHPP, MEOHP, MEHP, cxMinCH, cxMiNP, ohMiNP, MEP, MOHiBP]. Spearman's partial correlations were adjusted for age, parity and BMI.Results: Significant associations were discovered between multiple lifestyle factors and concentrations of EDCs in ovarian follicular fluid. After correcting p values for multiple testing, frequent use of perfume was associated with MEP (correlation rho = 0.41 (confidence interval 0.21-0.47), p < 0.001); hens' egg consumption was positively associated with PFOS (rho = 0.30 (0.15-0.43), p = 0.007) and PFUnDA (rho = 0.27 (0.12-0.40), p = 0.036). White fish consumption was positively associated with PFUnDA (rho = 0.34 (0.20-0.47), p < 0.001) and PFDA (rho = 0.27 (0.13-0.41), p = 0.028). More correlations were discovered when considering the raw uncorrected p values. Altogether, our results suggest that multiple lifestyle variables affect chemical contamination of follicular fluid.Impact statement: This study shows how lifestyle factors correlate with the level of contamination in the ovary by both persistent and semi-persistent chemicals in women of reproductive age. Subsequently, these data can be used to form recommendations regarding lifestyle to mitigate possible negative health outcomes and fertility problems associated with chemical exposure, and to inform chemical policy decision making. Our study can also help form the basis for the design of larger observational and intervention studies to examine possible effects of lifestyle changes on exposure levels, and to unravel the complex interactions between biological factors, lifestyle and chemical exposures in more detail.