Air pollution doesn’t only affect your lungs as new research suggests air quality may also be linked to a decrease in the number of eggs in women’s ovaries. It has long been known that environmental factors impact our reproductive systems, and multiple studies linked low sperm count with environmental indicators, but fewer examine the connection to ovaries.

This newest study, presented at the European Society of Human Reproduction and Embryology is the first to look at the prevalence of eggs and not just fertility. Italian researchers collected hormone samples from 1,300 Italian women and compared their levels of the AMH hormone to air quality metrics. The AMH hormone typically signals a woman’s egg “reserves” but can also fluctuate depending on the woman’s age, genetics and if they are a smoker.

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Researchers found that lower AMH hormone levels were associated with higher air pollution indices. This suggests that air pollution may be connected to lower egg count in ovaries. However, researchers also recognize that often air pollution is concentrated in areas with lower income and other environmental justice issues, therefore there are likely confounding factors that also impact women’s ovaries within these areas. The study also did not measure direct exposure to air pollution, only indirect exposure via the average air pollution index at the participants’ home address.

“Living in an area associated with high levels of air pollutants in our study increased the risk of severely reduced ovarian reserve by a factor of two or three,” said Dr. Antonio La Marca, who led the research. Other studies have similarly linked air quality with womens’ reproductive health, including one study that links pollution with irregular menstrual cycles and another that connected ozone pollution with decreased fertility.

More research is needed to clarify the findings and determine if this is a temporary or permanent effect for women.

Via The Guardian

Image via Ian MacNicol