These days, it’s not uncommon for women to want to put child-rearing on hold while they focus on pursuing their own interests or professional careers. This means that many women are opting to have kids later in life—however, women’s reproductive biology differs from men’s because they are born with all of the eggs they will ever have, while men’s reproductive organs, on the other hand, are able to regenerate millions of new materials every day.
This means that the quality of the chromosomes and DNA within women’s eggs declines with age, which is why the average woman in her early twenties has an 86 percent chance of becoming pregnant, and the average forty-year-old has only a 36 percent chance.
Well, thanks to a team of researchers from Hebrew University in Israel, this may not be a problem for much longer. The team applied an anti-viral treatment (specifically reverse-transcriptase inhibitors, which are antivirals that are used to treat viruses like HIV and HPV) to “reverse” the aging process of eggs, demonstrating that the novel treatment made the chromosomes in older eggs look more like those in younger eggs. The treated eggs had less damaged DNA and matured better in test tubes.
The development is still in its early stages and hasn’t been tested against fertilization, but these initial findings are promising and could provide a viable option for women over 40 who want to become mothers.
Modern medicine and motherhood
The team came to this solution by focusing on a key part of the aging process that hinders egg cells from maturing successfully as they age.
As a woman ages, her own DNA begins to harm the DNA in the egg cells by replicating themselves inside the cell, similar to how a virus attacks. Younger women’s bodies respond well against this kind of attack, however the response weakens with age.
“Because the attacking DNA behaves like a virus, we hypothesized that anti-viral medicine administered to eggs may reverse age them and rejuvenate them, and found in our lab that this is the case,” Hebrew University molecular biologist and lead researcher Dr. Michael Klutstein told The Times of Israel. “We tested hundreds of mouse eggs and then human eggs, which confirmed the hypothesis,” he added.
The researchers haven’t yet added sperm to the eggs to see if the “rejuvenated” mouse eggs have improved chances of reproduction, however they plan to do so shortly via in vitro fertilization. They have also acknowledged that some of the aging mechanisms have not been affected but his treatment, so they are still unsure of whether fertility will be improved. Nevertheless, the team hopes that their work will, in ten years time, give older women a chance to increase their fertility and become mothers.