Abstract Body
Background: Anti-Müllerian hormone (AMH) levels are a marker of ovarian reserve and are indicative of a woman’s reproductive life span. Although exposure to indoor air pollution has been associated with diminished AMH, little is known about the association between ambient air pollution and ovarian reserve especially in a population not seeking fertility treatments. Methods: For 4,696 Sister Study participants, residential annual average exposure to PM2.5, PM10 , and NO2 was assessed using land-use regression models and kriging. We estimated distance to the nearest major road for both adult and childhood residences. Serum AMH was measured using ultrasensitive AMH ELISA and picoAMH ELISA kits in 1,322 premenopausal women. We also included postmenopausal women (N = 3,374) in our analyses to address potential selection bias. Inverse probability weighting was used to account for selection into the study. For postmenopausal women or women with AMH values below the limit of detection (LOD), AMH values were imputed as LOD/2. To account for the non-detects, reverse Cox regression modeling with restricted cubic spline adjustment for age was used to estimate hazard ratios (HRs) for the association between ambient air pollution and distance to major roadway and AMH levels. Results: Overall, we saw no consistent association between air pollution exposure or proximity to roadways and AMH levels. An interquartile range (IQR) increase in NO2 was associated with slightly higher AMH levels (HR = 1.10, 95% CI: 0.99, 1.22). However, among the women not currently using oral contraceptives (which may impact measured AMH levels), an IQR increase in PM2.5 was associated with lower AMH levels (HR = 0.88, 95% CI: 0.77-0.99). Conclusions: We saw little evidence to support an association between outdoor air pollution and diminished ovarian reserve in women of older reproductive age, except possibly among women who were not current users of hormonal contraceptives.
