Environment/Climate Change
Associations of maternal PFAS exposure with birthweight and placental weight in a New York City-based birth cohort Eleanor Medley* Eleanor Medley Medley Medley Medley Medley Department of Population Health, NYU Grossman School of Medicine
Exposure to per- and polyfluoroalkyl substances (PFAS) has been previously associated with lower birthweight, but less is known about how PFAS may impact the placenta. We investigated associations of maternal PFAS exposure with birthweight, placental weight, and their relation in the New York University Children’s Health and Environment Study. We measured concentrations of 13 PFAS in prenatal serum collected between 2017-2020 (n=500). Analyses included 7 PFAS detected in >50% of samples: 5 long-chain compounds (PFOS, PFOA, PFDA, PFNA, PFUnDA), and 2 shorter-chain replacements (PFHxS, PFBS). Subsets of 498 and 247 participants with available birthweight and placental weight data, respectively, constituted the analytic samples. We computed birthweight-for-gestational age z-scores with INTERGROWTH-21st, and the residuals of birthweight regressed on placental weight and gestational age (eBW) to estimate placental efficiency. We modeled associations of individual PFAS with birthweight z-scores (BWGA), placental weight, and eBW using linear regression adjusted for maternal age, race/ethnicity, parity, BMI, insurance status, and child sex. We estimated joint effects of the PFAS mixture on BWGA and placental weight using Bayesian Kernel Machine Regression (BKMR). In single-pollutant models, PFHxS was associated with lower BWGA (β -0.11 SD [-0.23, 0.00]), and PFUnDA and PFOA were associated with higher placental weight (β PFUnDA 14 g [1, 27], β PFOA 13 g [-6, 33]). PFHxS was associated with lower eBW, indicating lower placental efficiency. In BKMR analyses, long- and short-chain PFAS had similar posterior inclusion probabilities. Exposure-response functions resembled linear regression models. The overall effect of the PFAS mixture was associated with higher placental weight. These results suggest that maternal PFAS exposure may affect placental and fetal growth, supporting future investigation into potential impacts on placental structure and function.