# Exposure to per- and poly-fluoroalkyl substances and associations with embryo quality and adverse pregnancy outcomes: a prospective cohort study

## TL;DR

This study finds that exposure to certain industrial pollutants called PFASs is linked to higher miscarriage rates and lower live birth rates in women undergoing IVF, but does not affect embryo quality.

## Contribution

The study identifies specific PFAS chemicals associated with adverse pregnancy outcomes and uses advanced statistical models to assess their combined effects.

## Key findings

- PFAS exposure was not significantly associated with high-quality blastocyst rates.
- Exposure to PFASs was significantly linked to higher miscarriage rates and lower live birth rates.
- Perfluoro-n-butanoic acid (PFBA) was identified as a major contributor to these adverse outcomes.

## Abstract

Per- and poly-fluoroalkyl substances (PFASs) are a group of synthetized industrial pollutants which have been detected worldwide in both environment and humans and gradually raised public health concerns. Previous studies suggested that PFASs had reproductive toxicity and may do harm to pregnancy and children. However, it is still uncertain that whether effect of PFAS exposure on offsprings begins from embryo quality or post-implantation pregnancy outcomes. This study explores the association between exposure to PFASs and embryo quality or pregnancy outcomes to promote maternal–infant health.

This study included 246 women who underwent their first in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles from July 2017 to August 2018 and measured concentrations of 23 PFAS congeners of follicular fluid samples. Generalized linear regression model with ln-transformed concentration values was performed to evaluate the association between individual PFAS congener and embryo quality and pregnancy outcomes. Weight quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were used to estimate mixed effect of PFAS exposure on the above outcomes.

PFAS exposure had no significant association with high-quality blastocyst rate. Whereas, PFAS exposure had significantly adverse effect on miscarriage and live birth rate with the predominant risk of perfluoro-n-butanoic acid (PFBA) (For miscarriage, Q4 vs. Q1 OR: 6.44 (95%CI: 1.47, 33.72), Adjusted p = 0.03; For live birth, Q4 vs. Q1 OR: 0.35 (95%CI: 0.14, 0.82), Adjusted p = 0.04). BKMR model also suggested that there was potential joint effect between mixed PFAS chemicals and miscarriage or live birth.

For women undergoing IVF/ICSI, exposure to PFASs was associated with higher miscarriage and lower live birth rate but had no adverse effect on embryo quality.