Mixed and single effects of endocrine disrupting chemicals in follicular fluid on likelihood of diminished ovarian reserve: A case-control study

Abstract

Endocrine-disrupting chemicals (EDCs) are a group of the most widely spread pollutants. Their impacts on reproductive health have become public concerns. Diminished ovarian reserve (DOR) is a disorder of ovarian function. Associations between EDC and DOR have been inconsistent. Very little research investigated the joint effects of multiple EDCs. Here, we performed a case-control study among 64 DOR women and 86 controls. Twenty-one EDC chemicals were assessed in follicular fluid, including parabens, phenols, phthalates and poly-fluoroalkyl substances. Both mixed and single effects of EDCs on DOR were evaluated and validated with a Bayesian kernel machine and logistic regressions. We found that the likelihood of DOR significantly increased with rising levels of the 21-EDC mixture, with an odds ratio (OR) and 95% confidence interval (CI) of 2.12 (1.17-3.83) for the 75th percentile compared to its median level. The overall effect was higher than effects of each subgroup. BP4, MECPP, and PFHxA were driving the association to the mixture, and their single effects were validated, with individual ORs of 8.25 (95%CI:3.45-12.21), 1.92 (95%CI:1.02-4.09), and 1.84 (95%CI:1.08-3.86), respectively. In conclusion, we provided new pollutant markers for DOR and emphasized the importance of the effects of EDC mixtures on female reproductive health.

Keywords: Bayesian kernel machine regression (BKMR); Diminished ovarian reserve (DOR); Endocrine disrupting chemicals (EDC); Joint effect; Single effect.