3 weeks Ago
Research links winter spikes in PM2.5 air pollution to lower pregnancy and live birth rates in ART patients, raising concerns over fertility impacts of environmental exposure. Study: Environmental pollution and human fertility: investigating the relationship between PM2.
5 exposure and assisted reproductive technology outcomes . Image Credit: Shutterstock AI Generator / Shutterstock.com A recent study published in BMC Public Health explores the impact of seasonal fluctuations in fine particulate matter (PM) with a diameter of 2.
5 μm or less (PM 2.5 ) pollution on the outcomes of assisted reproductive technology (ART). How does air pollution impact fertility? The success of ART procedures can be affected by various factors, some of which include age, lifestyle, and genetics.
To date, the impact of PM 2.5 exposure on reproductive health, particularly ART outcomes, remains unclear. Long-term exposure to PM 2.
5 air pollution significantly increases the risk of developing cardiovascular and respiratory diseases. Current evidence suggests that air pollution can also lead to reduced fertility rates and a greater risk of pregnancy complications such as reduced life birth rates. As a result, clinicians will often recommend limiting exposure to air pollution at least three months before initiating in vitro fertilization (IVF) treatment.
Despite these observations, few studies have investigation the impact of ambient PM 2.5 levels on ART outcomes across seasons. About the study The current study was conducted at Shangqiu’s First People’s Hospital and included 13,476 patients who were treated for infertility issues with ART between February 2018 and December 2022.
There were approximately 4,000 patients each with spring and summer treatments, as compared to 2,300 and 3,400 patients treated during winter and autumn, respectively. The period during which PM 2.5 levels were considered began at controlled ovarian stimulation and ended within 30 days of the pregnancy test.
This period is considered a critical window of success for optimal oocyte and embryo development and implantation, respectively. Study findings With comparable gonadotropin use, multiple reproductive outcomes changed during all seasons and correlated with PM 2.5 exposure.
These included both early stages in the ART process like the number of oocytes and how many entered metaphase II (MII), the number of embryos suitable for transfer, and the number of good-quality embryos. After adjusting for age and expected changes in seasonal rates, a significant negative association was observed between PM 2.5 exposure and both pregnancy and life birth rates.
PM 2.5 exposure did not significantly affect miscarriage rates. As compared to winter months, the spring and summer seasons were associated with a greater number of pregnancy rates for each transfer, with this difference statistically significant between winter and spring months.
Live birth rates were also higher during the spring, summer, and autumn months. The findings of this study demonstrate a consistent adverse relationship between PM 2.5 levels and important ART outcomes, including oocyte number, MII oocyte number, transferable embryos, and good-quality embros.
” Dissecting the mechanisms of PM 2.5 -mediated reproductive toxicity Following the inhalation or ingestion of PM 2.5 , these particles can enter systemic circulation to reach the embryos and negatively impact optimal oocyte and embryo development.
Several studies have reported that PM 2.5 exposure induces the production of reactive oxygen species (ROS), mitochondrial dysfunction, DNA damage, and early apoptosis, all of which can diminish the quality of oocytes and prevent embryo implantation. Related Stories Study links childhood air pollution exposure to weaker brain connections Study reveals how air pollution contributes to Alzheimer's disease The link between air pollution and lower respiratory infections in adults Within the female reproductive system, PM 2.
5 exposure can also damage endometrial cells, thereby inducing oxidative stress and inflammation that is not conducive for embryo attachment to the endometrial lining. PM 2.5 exposure may also alter the expression of adhesion molecules, growth factors, and other substrates that are essential for successful embryo implantation.
PM 2.5 exerts toxic effects on oocytes and embryos, directly disrupting cellular processes and ultimately impairing fertility outcomes.” In addition to the toxic effects of PM 2.
5 exposure on maternal reproductive health, various aspects of male fertility can similarly be impacted by PM 2.5. Previously, researchers have reported that PM 2.
5 exposure reduces sperm quality and density by targeting the forehead box protein O1 (FOXO1), in addition to reducing testosterone levels and increasing inflammation within the testes. Conclusions Taken together, the study findings indicate a seasonal influence on the effects PM 2.5 air pollution on ART outcomes, as live birth rates were significantly lower during the winter months as compared to other seasons of the year.
Although the reproductive toxicity associated with PM 2.5 is likely multifactorial, additional studies are needed to elucidate the exact mechanisms by which PM 2.5 interferes with the potential success of ART treatments.
Li, F., Duan, X., Li, M.
, et al . (2025). Environmental pollution and human fertility: investigating the relationship between PM2.
5 exposure and assisted reproductive technology outcomes. BMC Public Health . doi:10.
1186/s12889-025-22518-5 ..
