Time-Varying Exposure to Air Pollution and Outcomes of in Vitro Fertilization among Couples from a Fertility Clinic

Abstract

Background:A few studies suggest that air pollution may decrease fertility, but prospective studies and examinations of windows of susceptibility remain unclear.Objective:We aimed to examine the association between time-varying exposure to nitrogen dioxide (NO2), ozone (normalO3), fine particulate matter <2.5μm (PM2.5), and black carbon (BC) on in vitro fertilization (IVF) outcomes.Methods:We included 345 women (522 IVF cycles) for the NO2, normalO3, and PM2.5 analyses and 339 women (512 IVF cycles) for the BC analysis enrolled in a prospective cohort at a Boston fertility center (2004–2015). We used validated spatiotemporal models to estimate daily residential exposure to NO2, normalO3, PM2.5, and BC. Multivariable discrete time Cox proportional hazards models with four periods [ovarian stimulation (OS), oocyte retrieval to embryo transfer (ET), ET to implantation, implantation to live birth] estimated odds ratios (OR) and 95% confidence intervals (CI) of failing at IVF. Time-dependent interactions were used to identify vulnerable periods.Results:An interquartile range (IQR) increase in NO2, PM2.5, and BC throughout the IVF cycle was associated with an elevated odds of failing at IVF prior to live birth (OR=1.08, 95% CI: 0.95, 1.23 for NO2; OR=1.06, 95% CI: 0.88, 1.28 for PM2.5; and OR=1.16, 95% CI: 0.96, 1.41 for BC). This relationship significantly varied across the IVF cycle such that the association with higher exposure to air pollution during OS was strongest for early IVF failures. An IQR increase in NO2, PM2.5, and BC exposure during OS was associated with 1.42 (95% CI: 1.20, 1.69), 1.26 (95% CI: 0.96, 1.67), and 1.23 (95% CI: 0.96, 1.59) times the odds of failing prior to oocyte retrieval, and 1.32 (95% CI: 1.13, 1.54), 1.27 (95% CI: 0.98, 1.65), and 1.32 (95% CI: 1.10, 1.59) times the odds of failing prior to ET.Conclusion:Increased exposure to traffic-related pollutants was associated with higher odds of early IVF failure. https://doi.org/10.1289/EHP4601

Follicular fluid anti-Müllerian hormone (AMH) concentrations and outcomes of in vitro fertilization cycles with fresh embryo transfer among women at a fertility center

“…Patients then underwent controlled ovarian hyperstimulation by luteal-phase gonadotropin-releasing hormone (GnRH) agonist, GnRH antagonist downregulation, or GnRH agonist flare protocol, with follicular synchronization and pituitary downregulation as clinically indicated and previously described [17,[19][20][21]. During treatment with recombinant gonadotropins (follitropin beta, Follistim, Merck, Kenilworth, NJ, or follitropin alpha, Gonal-F, EMD-Serono; and m e n o t r o p i n s , M e n o p u r o r R e p r o n e x , F e r r i n g Pharmaceuticals, Parsippany, NJ), patients were serially monitored with transvaginal ultrasound and serum estradiol (E 2 ) to assess follicular measurements and endometrial thickness.…”

Environmental Factors Involved in Maternal Morbidity and Mortality

“…NO 2 and PM 2.5 are associated with increased ART cycle failure rates. 13 Carbon monoxide 14 and PM 2.5 15 are associated with decreased conception rates. Decreased live birth rates are associated with NO 2 , 12,15,16 SO 2 , 17 ozone, 15 and PM 2.5 .…”

“…Decreased live birth rates are associated with NO 2 , 12,15,16 SO 2 , 17 ozone, 15 and PM 2.5 . 13 An ecologic association between air pollutant peaks and monthly in vitro fertilization pregnancy failure rates has been observed. 11…”

Association Between Ambient Air Pollutants Exposure and Preterm Birth in Women Who Underwent in vitro Fertilization: A Retrospective Cohort Study From Hangzhou, China

“…Since 1978, more than five million children were born through assisted reproductive technology (ART) treatment ( 15 ). This provides the opportunity for a novel evaluation of the effects of air pollutants because it is possible to observe many early reproductive outcomes, such as embryo implantation that can't be observed in natural pregnancy ( 16 ). Furthermore, the timing of conception is known with certainty because key events in the IVF treatment are timed and trigger by a physician, exact exposure periods of air pollutants can be determined ( 16 , 17 ).…”

“…This provides the opportunity for a novel evaluation of the effects of air pollutants because it is possible to observe many early reproductive outcomes, such as embryo implantation that can't be observed in natural pregnancy ( 16 ). Furthermore, the timing of conception is known with certainty because key events in the IVF treatment are timed and trigger by a physician, exact exposure periods of air pollutants can be determined ( 16 , 17 ). To date, several studies have reported the association between air pollutants exposure and follicle growth, a reduced rate of implantation, pregnancy or live birth in women who underwent ART treatment, but the results were inconsistent ( 16 , 18 – 21 ).…”