Associations of prenatal exposure to legacy and emerging PFAS with anogenital distance growth trajectories during early childhood: A prospective cohort study.

The effect of prenatal exposure to emerging Per- and polyfluoroalkyl substances (PFAS) on the trajectory of reproductive development has not been reported. Based on the Shanghai Minhang Birth Cohort, we aimed to examine the associations between prenatal exposure to legacy and emerging PFAS and the trajectory of the anogenital distance (AGD). A group-based trajectory model was used to characterize AGD trajectories. Multiple logistic and Bayesian Kernel Machine Regression models were used to explore the associations between prenatal PFAS exposure and the AGD trajectories. The findings showed that prenatal exposure to perfluorobutanesulfonic acid (PFBS), an emerging PFAS, was associated with decreased odds of being in the "Rapid Growth" group of AGDAS (OR = 0.44, 95 % CI: 0.20-0.98) among boys. Perfluorohexane sulfonic acid (PFHxS), perfluorotridecanoic acid (PFTrDA), perfluorododecanoic acid (PFDoDA) exposure in the highest tertile, and perfluorohexanoic acid (PFHxA) in the medium tertile were associated with the higher odds of being in the AGDAF "Rapid Growth" trajectory among girls, and the corresponding ORs were 2.98 (95 % CI: 0.97-9.19), 3.16 (95 % CI: 1.08-9.28), 3.27 (95 % CI: 0.99-10.81), and 3.60 (95 % CI: 1.05-12.28), respectively. This study provides preliminary evidence that prenatal legacy and emerging PFAS exposure are associated with AGD growth trajectories and that these effects exhibited sexual dimorphism.