Protecting laboratory air quality and comparing clinical assisted reproductive technology cycle outcomes before, during and after wildfire events: a retrospective cohort study

Introduction Climate change is increasing the frequency and severity of wildfires globally, leading to elevated air pollution and potential human health risks. This study examines whether large-scale wildfires impact indoor air quality within fertility clinics and affect assisted reproductive technology (ART) outcomes. Methods A retrospective cohort study of 1,647 ART cycles (IVF and/or ICSI) at Number One Fertility clinics in Victoria, Australia, explored cycles occurring before, during, and after the 2019–2020 ‘Black Summer’ wildfires. ART outcomes were compared across quartiles in 2019–2020 and stratified by maternal age (<38 or ≥38 years). Concentrations of particulate matter (PM 2.5 , PM 10 , and total PM) were measured indoors and outdoors at three clinical sites during and following wildfire exposure. Results Results indicated that PM concentrations were consistently lower indoors than outdoors at all clinic locations. Embryology laboratories maintained negligible particulate levels despite elevated outdoor pollution during the wildfires. No significant differences in ART outcomes were observed across cycles performed before, during, or after the wildfire period. Key outcomes such as oocyte yield, fertilisation rates, embryo utilization, clinical pregnancy, and live birth rates remained unaffected. Discussion This study highlights the effectiveness of air filtration systems in maintaining air quality within embryology laboratories during wildfire events and emphasizes the importance of such controls in fertility clinics. Future research is needed to investigate the long-term reproductive effects of environmental exposures on fertility, ART cycles and pregnancy outcomes.