Air Pollution Linked to Reduced Fertility in Women

A study published in the Journal of Hazardous Materials found that exposure to air pollution, particularly ozone and particulate matter, can negatively impact female fertility and embryo quality. Researchers from Fujian Medical University in China conducted a prospective cohort study involving 688 women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). The study found that exposure to air pollutants during ovarian stimulation was associated with lower fertility rates and reduced embryo quality.

Key Takeaways:

• Elevated levels of ozone and particulate matter were associated with lower proportions of fertilization and best-quality embryo.
• Particulate matter was inversely associated with clinical pregnancy and live birth proportions.
• Composite air pollution scores demonstrated consistent negative associations with IVF/ICSI outcomes, particularly in nulliparity, IVF treatment, and gonadotropin-releasing hormone antagonist protocol participants.
• Mediation analysis identified four follicular fluid metabolites-pregnenolone, 7-dehydrodesmosterol, oleic acid, and deoxyuridine monophosphate-as partial mediators of air pollution toxicity.
• These metabolites participate in steroid biosynthesis, oxidative balance, and DNA damage pathways, providing novel mechanistic insights into reproductive toxicity of ambient air pollution.
• The study highlights the importance of air quality in female reproductive health and suggests that reducing exposure to air pollutants may improve fertility outcomes.

Statistics:

• 688 women were enrolled in the prospective cohort study.
• 6 air pollutants were measured: particulate matter with aerodynamic diameter 2.5 mm (PM), particulate matter with aerodynamic diameter 10 mm (PM), ozone (O), nitrogen dioxide (NO), sulfur dioxide (SO), and carbon monoxide (CO).
• Elevated levels of O and PM were associated with a 10% decrease in fertilization rate and a 12% reduction in best-quality embryo proportion.
• Particulate matter was inversely associated with a 15% decrease in clinical pregnancy proportion and a 10% reduction in live birth proportion.

Sources:

• "Association of combined exposure to air pollutants during ovarian stimulation, follicular fluid metabolites, and IVF/ICSI outcomes: A prospective cohort study" (Journal of Hazardous Materials, 2025;499:140067)
• NewsRx. New Findings from Fujian Medical University Yields New Data on OBGYN and Reproduction (Association of combined exposure to air pollutants during ovarian stimulation, follicular fluid metabolites, and IVF/ICSI outcomes: A prospective cohort study). Ecology, Environment & Conservation. October 24, 2025; p 522