Women could be mothers in their 50s, say Israeli scientists who have successfully ‘re-aged’ human eggs.
In a major breakthrough, Israeli researchers managed to effectively resemble eggs from 40-year-old women to those from 20-year-olds.
Females are born with all of their eggs, but they deteriorate over time, making older eggs more difficult to fertilize.
While the average woman in her early 20s has an 80% chance of conceiving naturally within a year, that chance halves by the age of 40.
Only a few hundred women in the UK become mothers in their 50s each year.
Scientists from the Hebrew University of Jerusalem have shown that the deterioration could be reversed with an antiviral drug used to treat HIV patients.
It is thought to work by preventing DNA damage that occurs during the aging process with a drug that blocks genetic damage during viral infections.
Following this success, the team now plans to test it on animals and eventually humans. It’s also hoped the treatment could reduce the risk of miscarriage and birth defects, which are more common in older mothers.
During the aging process in a human egg, parts of its DNA can begin to attack other areas, much like viruses can multiply. To stop this, the scientists theorized that an antiviral called a reverse transcriptase inhibitor, used to prevent DNA damage in viral infections, might help.
“Many women are trying to conceive in their 40s or older, and we think doing so could actually increase their fertility,” said Dr. Michael Klustein, the molecular biologist who led the research, told the Times of Israel.
“Within 10 years, we hope to use antiviral drugs to increase fertility in older women,” he said.
Klustein explained that the attacking DNA behaves like a virus, so the antiviral medicine given to the eggs reverses their aging.
The drug was first tested on hundreds of mouse embryos before being used on leftover human embryos from IVF treatments. The team claimed in a press release that the older mouse eggs that were treated “reverted to their former juvenile selves.”
A 2020 Office for National Statistics (ONS) study showed that women decide to have children much later than previous generations.
In the UK, the median age of first-time mothers is now 29 – compared with 23 in the 1970s – and many delay having children well into their 30s.
The change can be attributed to greater choice and autonomy, but also to financial concerns. However, studies suggest that by the time a woman is over 40, the chance of becoming pregnant drops to just five percent.
To get around this, many women are now having eggs frozen when they are younger in preparation for later fertility treatment. Around 50,000 women seek fertility treatment in the UK each year, compared to over 90,000 in the US.
Success rates for IVF treatment are around 25% – or one in four embryos – for women between the ages of 35 and 37. For those under 35, success rates are around 32%
However, the scientists behind the study emphasized that they have not yet tested the introduction of sperm into the treated eggs, so it remains to be proven whether this improves fertility.
The study was published in the journal “Aging Cell”.
MORE : Chloe Madeley reveals two years of struggle to conceive: ‘It was hard to see everyone around me getting pregnant’
MORE : A virgin mouse gave birth to a litter of baby mice
Get the top news, feel-good stories, analysis and more
https://metro.co.uk/2022/03/09/women-could-be-mothers-at-50-thanks-to-reverse-aged-human-eggs-16244739/ Thanks to "reversed" human eggs, women in their 50s could be mothers