Genetic markers in women who have given birth indicate that cell aging is accelerating.

Having a baby inevitably brings about significant changes in a woman's body and mind, but the lifelong impact of being a mother can be far greater than we think.
an analysis of the DNA of about 2,000 women of childbearing age in the United States showed signs of changing the genetic markers of those who had given birth, suggesting that their cells are aging faster.
the study was published in Human Reproduction. "We were very surprised to find that having a baby is equivalent to accelerating cell aging for 11 years," said Anna Pollack, an epidemiologist at George Mason University in the United States at
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" Pollack and her team analyzed data from the National Institute of Health and Nutrition Examinations (NHANES).
when they analyzed data from 1999-2002, the NHANES survey included genetic marker measurements of telomeres.
they found something unusual.
telomeres are a molecular region that is a "cap" that snaps to the end of chromosomes to protect genetic information in cells from being destroyed over time, and some have speculated that telomeres can also prevent chromosomes from being exposed to things harmful to health.
in this case, telomere length is considered a marker of actual age at the cellular level, and the longer the telomeres, the better the health, as shorter telomeres may be associated with diseases such as cancer, heart disease and cognitive decline.
Now, we've found that having children can also cause telomeres to become shorter.
in the study, they found that women who had at least one child had an average of 4.2 percent shorter chromosome telomeres than those who had not, after adjusting for factors such as age, race, education, and smoking. the adjusted average difference in
meant that women who gave birth lacked 116 base pairs, which the researchers explained was equivalent to about 11 years of accelerated cellular aging.
surprisingly, the birth-related telomeres are even shorter even faster than previous studies have observed, which tested the relationship between smoking (equivalent to 4.6 years of cell aging) and obesity (equivalent to 8.8 years of cell aging) and telomeres.
, the degree of telomere shortening in the study appeared to be related to the number of children a woman had. "We found that women who had more than five children had shorter telomeres and shorter telomeres than women who had not had children," said Pollack,
. "It's important to note that this is just an observational study, and we don't draw any causal conclusions, but just a correlation,"
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at least one study has come to the opposite conclusion, and a 2016 study in the rural area of Kaqchikel Mayan, Guatemala, found that women with more surviving children have longer telomeres, suggesting that having children prevents women from aging.
past studies have used cell aging to quantify the extent to which base-to-telomeres are shortened, and researchers believe that having children leads to only 4.5 years of early aging.
at least one researcher who wasn't involved in the study believes that having a baby can lead to up to three years of biological aging.
as to what causes the telomeres shortened in the sample, the researchers speculate that it may be due to the stress of caring for children, but given that there is little research in the field, they recommend caution. "Our study isn't about telling people not to have children,"
Pollack said.
"Scientists are studying what the cause is, and we need rational advice."
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