Air pollution has been found to affect a marker of female fertility.
Ovarian reserve, a term widely adopted to reflect the number of resting follicles in the ovary – and therefore a marker of potential female fertility – has been found in a large-scale study to be adversely affected by high levels of air pollution.
The findings of the study are based on hormone measurements taken from more than 1,300 Italian women.
The hormone in this case – anti-Mullerian hormone or AMH – is secreted by cells in the ovary and is widely recognised as a reliable circulating marker of ovarian reserve.
Professor Antonio La Marca, from the University of Modena and Reggio Emilia, presented the study at the European Society of Human Reproduction and Embryology (Eshre) annual meeting in Vienna.
The analysis was completed with environmental data and a geo-localisation estimate based on each patient’s residence.
The assessment of environmental exposure considered daily particulate matter (PM) and values of nitrogen dioxide (NO2), a polluting gas which gets into the air from burning fuel.
Results from the 1463 AMH measurements collected from 1,318 women firstly showed, as expected, that serum AMH levels after the age of 25 were inversely and significantly related to the women’s age.
However, it was also found that AMH levels were inversely and significantly related to environmental pollutants.
While noting that the study again confirms that age is the most important determinant of AMH concentration in women, Professor La Marca emphasised that other factors such as smoking, body weight and long-term hormonal contraception are already recognised as having an impact on AMH.
Similarly, he said environmental pollutants may also have a significant effect in determining circulating levels of AMH.
“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,” he said.