Ambient air pollutant exposure and in vitro fertilization treatment outcomes in Zhengzhou, China

Objective: To study the association between ambient air pollutant exposure during the follicular phase and in vitro fertilization (IVF) outcomes. Design: A single-center retrospective analysis. Setting: Henan Province, China. Patients: Patients (n = 6659) living in Zhengzhou, Henan Province in central China who underwent their first IVF cycle at the First Affiliated Hospital of Zhengzhou University between 2013 and 2019 were included for analysis. Intervention: None. Main outcome measure: The relationships between PM2.5, PM10, and AQI (Air Quality Index) with IVF outcomes during the follicular phase (period I, 85 days before oocyte retrieval; period II, gonadotrophin start to oocyte retrieval). Results: Compared with the bottom tertile, exposure to the top PM2.5 and PM10 tertiles during period I was associated with decreased clinical pregnancy (PM2.5: adjusted odds ratio [OR], 0.838%, and 95% confidence interval [CI], 0.723 and 0.971; PM10: adjusted OR, 0.818%, and 95% CI, 0.705 and 0.950), and decreased live birth rate (PM2.5: adjusted odds ratio [OR], 0.852%, and 95% confidence interval [CI], 0.736 and 0.987; PM10: adjusted OR, 0.850%, and 95% CI, 0.733 and 0.986), and exposure to the top PM2.5 tertile during period II adversely affected clinical pregnancy and the live birth rate (adjusted OR, 0.824%, and 95% CI, 0.711 and 0.955; adjusted OR, 0.817%, and 95% CI, 0.706 and 0.945). Compared with the bottom PM10 tertile, exposure to the middle PM10 tertile in period II showed decreased clinical pregnancies and live births (adjusted OR, 0.844; 95% CI, 0.729 and 0.978, adjusted OR, 0.846; 95% CI, 0.731 and 0.979). The PM10 level during period II of the follicular phase tend to adversely affect live birth rate, but the tendency did not reach significance (P = 0.051). Conclusion: Exposure to PM2.5 and PM10 before oocyte retrieval has an adverse effect on IVF outcomes. Capsule: Exposure to PM2.5 and PM10 before oocyte retrieval has an adverse effect on IVF outcomes.