Why does fertility decrease after a certain age for women? The response in some specific genes

We women are often treated with the expiration date. Especially when it comes to fertility. We are told that after the age of 36, fertility drops drastically even if by the age of 30 things start to get worse.

Yet despite this, the age at which the first child is born is always higher. Every year the ISTAT data on birth and fertility are a confirmation of this.

Almost 45% become mothers for the first time over the age of 30.

With the consequence that it takes several months to be able to conceive a child and often you have to resort to some help to encourage it. Maternal and/or fetal complications are also greater after a certain age.

Scientists recently found a possible reason why women gradually lose their fertility   thanks to research published in Science Translational Medicine  that could pave the way for specific treatments to extend women’s childbearing years beyond their biological limit.

The research looked at oocytes produced by women who had undergone treatments to increase their fertility. The functionality of several DNA repair genes has been found to decrease with age . This decline would be accelerated in women towards the age of menopause and this seems to clarify why after the age of 40 the woman is at the limit of her fertility.

When the genes that repair DNA, which are contained in the chromosomes of egg cells, no longer do their job as they should, the oocytes are altered and rapidly undergo a process of cell death.

The results therefore suggest the possibility of extending a woman’s fertility by developing a treatment that preserves the functionality of DNA repair genes within egg cells.

Researchers are already testing certain substances in the laboratory for this purpose and such a treatment could be able to extend a woman’s ability to have children up to age 50.

Search results

Researchers set about studying these particular genes after it was discovered that women at risk of breast cancer because they carried the BRCA1 gene mutation were less sensitive to drugs that were used to stimulate the ovary to produce eggs in procedures of fertility preservation.

Basically, women with the BRCA1 gene mutation had produced fewer oocytes under stimulation than those without the mutation.

BRCA1 is a DNA repair gene, and therefore researchers have begun to look more broadly at the role of other female DNA repair genes in relation to fertility.

The oocytes of 24 women aged between 24 and 41 years were examined and found that the BRCA1 gene and 3 other DNA repair genes were much less active in egg cells in older women than in older women. younger. This therefore indicates that over time, genes of this type gradually lose their ability to repair DNA damage at the level of egg cells.

Women are born with around 1 million eggs in their ovaries, said Prof. Okay, one of the study’s authors, and the number gradually decreases over time. Yet when women reach their 40s the eggs begin to degrade at a much faster rate, for reasons that have long been mysterious. At age 37, a woman has perhaps only 25,000 egg cells left.

The researchers also looked at egg cell levels in women with the BRCA1 gene mutation and compared them to an age-matched control group of women without the genetic mutation. Women with the BRCA1 mutation have accelerated aging of their egg cells and it would therefore be necessary for these women to try to have children before the age of 35-36