Adverse birth outcomes related to concentrations of per- and polyfluoroalkyl substances (PFAS) in maternal blood collected from pregnant women in 1960-1966

Background: Prior animal and epidemiological studies suggest that per-and polyfluoroalkyl substances (PFAS) exposure may be associated with reduced birth weight. However, results from prior studies evaluated a relatively small set of PFAS.Objectives: Determine associations of gestational PFAS concentrations in maternal serum samples banked for 60 years with birth outcomes.Methods: We used data from 97 pregnant women from Boston and Providence that enrolled in the Collaborative Perinatal Project (CPP) study (1960-1966). We quantified concentrations of 27 PFAS in maternal serum in pregnancy and measured infant weight, height and ponderal index at birth. Covariate-adjusted associations between 11 PFAS concentrations (>75% detection limits) and birth outcomes were estimated using linear regression methods.Results: Median concentrations of PFOA, PFNA, PFHxS, and PFOS were 6.189, 0.330, 14.432, and 38.170 ng/mL, respectively. We found that elevated PFAS concentrations during pregnancy were significantly associated with lower birth weight and ponderal index at birth, but no significant associations were found with birth length. Specifically, infants born to women with PFAS concentrations >= median levels had significantly lower birth weight (PFOS: beta =-0.323, P = 0.006; PFHxS: beta =-0.292, P = 0.015; PFOA: beta =-0.233, P = 0.03; PFHpS: beta =-0.239, P = 0.023; PFNA: beta =-0.239, P = 0.017). Similarly, women with PFAS concentrations >= median levels had significantly lower ponderal index (PFHxS: beta =-0.168, P = 0.020; PFHxA: beta =-0.148, P = 0.018).Conclusions: Using data from this US-based cohort study, we found that 1) maternal PFAS levels from the 1960s exceeded values in contemporaneous populations and 2) that gestational concentrations of certain PFAS were associated with lower birth weight and infant ponderal index. Additional studies with larger sample size are needed to further examine the associations of gestational exposure to individual PFAS and their mixtures with adverse birth outcomes.