Women’s decreased ability to produce healthy eggs as they become older may be due to excessive scarring and inflammation in their ovaries, reports a new Northwestern Medicine study in mice.
This is the first study to show the ovarian environment ages and that aging affects the quality of eggs it produces. These findings could result in new treatments that preserve fertility by delaying ovarian aging.
Most reproductive research focuses on women’s eggs and trying to understand why their number and quality deteriorate as a woman enters her forties. Deteriorating eggs contribute to infertility, miscarriages and birth defects.
But in this study scientists examined the reproductive age-related changes that occur in the environment in which the eggs develop, known as the ovarian stroma. The environment in which cells grow and develop can greatly influence their quality and function, but surprisingly little is known about how the ovarian stroma changes with age.
“Under the microscope, eggs from reproductively young and old animals may look identical, but the environment in which they are growing is completely different,” said lead study author Dr. Francesca Duncan, executive director of the Center for Reproductive Science at Northwestern University Feinberg School of Medicine. “Ovaries from reproductively old mice are fibrotic and inflamed. There is no way this environment won’t impact the eggs growing in it, and it very likely contributes to their decrease in quality.”
The study was published August 5 in the journal Reproduction. Dr. Duncan led the study when she was at the University of Kansas Medical Center.