Dietary Bisphenol A Exposure and Urinary Bisphenol A Levels During Late Pregnancy: Associations with Inflammatory and Oxidative Stress Biomarkers.

Background/Objectives: Pregnant women are vulnerable to endocrine-disrupting chemicals such as bisphenol A (BPA). However, associations of maternal BPA exposure with oxidative stress, inflammation, the Dietary Inflammatory Index (DII), dietary total antioxidant capacity (DTAC), and fetal/neonatal outcomes remain unclear. This study evaluated urinary and estimated dietary BPA exposure in conjunction with DII and DTAC during late pregnancy and examined their associations with maternal oxidative stress and inflammatory biomarkers and fetal/neonatal outcomes. Methods: This cross-sectional study included 86 third-trimester pregnant women at a Turkish tertiary hospital. BPA exposure was assessed using creatinine-adjusted urinary BPA concentrations and dietary intake estimated from 3-day dietary records and a food frequency questionnaire. Urinary and serum biomarkers were measured, and DII and DTAC scores calculated. Analyses included correlation, multivariable regression, and mediation. Results: Creatinine-adjusted urinary BPA correlated strongly with urinary 8-isoprostane (r = 0.694, p < 0.001) and 8-hydroxy-2'-deoxyguanosine (8-OHdG; r = 0.880, p < 0.001), but not after multivariable adjustment. Neither urinary nor dietary BPA exposure showed consistent adjusted associations with serum oxidative stress or inflammatory biomarkers or significant associations with fetal/neonatal outcomes. DII and DTAC correlated with selected inflammatory biomarkers, particularly TNF-α. Dietary BPA hazard quotients exceeded 1 using EFSA's updated 2023 tolerable daily intake, suggesting a potential health concern. Conclusions: Urinary BPA correlated strongly with urinary oxidative damage biomarkers, but not after multivariable adjustment. Neither urinary nor dietary BPA showed consistent adjusted associations with maternal oxidative stress or inflammatory biomarkers or significant associations with fetal/neonatal outcomes. DII and DTAC may be related to inflammatory biomarker variability in late pregnancy.