Association of PFAS exposure with maternal blood pressure and hypertension during pregnancy in the PROTECT cohort.

Per- and poly-fluoroalkyl substances (PFAS) have been associated with hypertension during pregnancy, although human studies are inconsistent. We examined this relationship in the Puerto Rico PROTECT cohort (N = 548). PFAS concentrations were measured in maternal serum at 16-20 weeks' gestation. Blood pressure (BP) was measured at two time points (16-20 and 24-28 weeks). We used multivariable linear regression to estimate associations between PFAS and continuous systolic and diastolic BP, pulse pressure (PP), and mean arterial pressure (MAP). We examined hypertension, high PP, and high MAP as binary outcomes in adjusted logistic regression models. Quantile g-computation was used to examine mixture effects, linear mixed models to examine longitudinal associations, and generalized additive models to examine nonlinearity. Perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexanesulfonic acid (PFHxS), and perfluorononanoic acid (PFNA) were detected in >50% of samples and modeled continuously, while perfluorodecanoic acid (PFDeA) and perfluoroundecanoic acid (PFUA) were detected in 25-50% of samples and modeled categorically (above/below detection limit). We found positive linear relationships between several individual PFAS and continuous BP measures, although estimates were imprecise and mixture effects varied. The exposure mixture (which included all six PFAS) was associated with higher odds of hypertension (OR = 2.14; 95% CI: 1.32-3.46) and to a lesser extent high MAP (OR = 1.50; 95% CI: 0.96-2.36) at 24-28 weeks and high PP at 16-20 weeks (OR = 1.54; 95% CI: 0.82-2.92). The odds of hypertension were higher among nulliparous women and those carrying female fetuses. Our findings indicate that 24-28 weeks' gestation may be a more sensitive period for high BP and MAP, while 16-20 weeks' gestation may be more sensitive for PP. Further research is warranted to confirm these findings.