“Women’s bodies are born with a fixed number of eggs”. So goes the accepted theory, which is understood to be one of the main causes for the limited lifespan of female fertility. However, research in its early stages has just emerged that may challenge this idea.
Evelyn Telfer, a professor of reproductive biology at the University of Edinburgh, led the study that produced these findings. Telfer was primarily investigating the effects of the chemotherapy drug, ABVD, which is used in the treatment of patients who suffer from Hodgkin Lymphoma cancer.
Telfer set out to understand why the drug, unlike most other forms of chemotherapy, didn’t cause infertility. To her surprise, she discovered that the samples taken from women being treated with ABVD had a higher density of eggs compared to those taken from healthy women.
The women taking ABVD had between double and four times the density of visible eggs. Not only this, but the eggs of the ABVD treated women appeared “younger” and “more like eggs seen in pre-pubescent girls”. “This was something remarkable and completely unexpected for us”, Telfer told The Guardian.
Telfer’s suggestion is that women’s bodies could develop new eggs. This reinforces previous studies in mice, involving the discovery of ovarian stem cells that were able to develop immature egg cells. However, it is important not to jump to conclusions about clinical applications. This was a very small study, involving cancer patients, and the results still need to be replicated in order to be confirmed.
Other experts in the field have reacted to Telfer’s suggestion with scepticism. David Albertini, laboratory director at the Centre for Human Reproduction warns, “there are too many other ways to explain the results”. An alternative explanation could be that the eggs were already there and that after the treatment they rose to the surface. Another is that the egg follicles simply split into two parts due to damage from the treatment.
It seems that the study raises a lot of questions. However, an attempt to answer these questions could be fruitful: if there is ground for further research, it could lead to new prospects for future fertility treatments.
Silvia Lazzaris is studying for an MSc in Science Communication
Image: Sperm an Ovum, CLIPAREA | Custom Media