Multiple pregnancies might make women's cells 'age' faster

July 25, 2018, Northwestern University
Credit: CC0 Public Domain

Multiple pregnancies might make women's cells age more quickly, a new Northwestern University study suggests.

Led by Calen Ryan and Christopher Kuzawa of Northwestern and Dan Eisenberg at the University of Washington, the research could help explain why women with many children tend to show signs of accelerated aging.

The findings, published this week in Scientific Reports, were reached by looking at two separate markers of cellular aging—telomere length and epigenetic age—in hundreds of young women with different reproductive histories in the Philippines.

"Telomere length and epigenetic age are cellular markers that independently predict mortality, and both appeared 'older' in women who had more pregnancies in their reproductive histories," said Ryan, lead author of the study and a doctoral student in biological anthropology at Northwestern. "Even after accounting for other factors that affect cellular aging, the number of pregnancies still came out on top."

Cellular aging was accelerated by between 0.5 and 2 years for each additional , a surprisingly large effect according to the researchers. Another finding they did not expect was the fact that women who were currently pregnant had cells that looked younger—not older—than predicted.

"Paradoxically, even though a woman's biological age was higher with each child that she had, if a woman was pregnant when the measurements were taken, her epigenetic age, and to a lesser extent her telomeres, looked 'younger' than predicted for her chronological age," said Kuzawa, senior author of the study and a professor of anthropology at Northwestern.

"It's an interesting situation in which pregnancy makes someone look temporarily 'young,' but there appears to be some lasting, cumulative relationship between the number of pregnancies and more accelerated biological age."

Researchers have known from historical records and epidemiological studies that women who have many children tend to have slightly shorter lives and succumb to different diseases than those who don't.

"What we didn't know was whether we could detect these kinds of effects using measures of cellular aging," Ryan said. "We also didn't know if we would even detect such effects among the relatively in this population, all of whom were 20 to 22 years old at the time."

"Our study was conducted in Cebu, Philippines, where energy can be limited, and physical workloads are frequently high," Ryan said. "In the high-resource environments typical of Europe and the U.S., the health risks associated with pregnancy might be lower."

Although there is good evidence that having more children, especially more than four or five, can increase the risk of certain diseases and shorten lifespan, researchers still don't really know why.

"Our study points to cellular changes during pregnancy, possibly related to adaptive changes in the mother's immune system as a possible explanation," said Kuzawa, also a faculty fellow at Northwestern's Institute for Policy Research. "There's still a lot we don't know. For instance, it's not clear whether these relationships will persist into later life as these women age. We also do not know whether these changes will actually lead to less favorable long-term health outcomes."

To answer these questions, a follow-up study on the same women 13 years after the first measurements, taken in 2005, is already underway.

"We want to see if we can replicate these findings longitudinally and if cells still look older later in life," Ryan said. "We still have a lot of questions to address that we hope will help us understand how factors like socioeconomic status and diet might contribute to costs of reproduction in ."

Explore further: Decrease in mean platelet counts seen during pregnancy

More information: "Reproduction predicts shorter telomere and epigenetic age acceleration among young adult women" published earlier this week in Scientific Reports.

Related Stories

Decrease in mean platelet counts seen during pregnancy

July 8, 2018
(HealthDay)—All women have a decrease in mean platelet counts during pregnancy, according to a study published in the July 5 issue of the New England Journal of Medicine.

Childhood poverty, poor support may drive up pregnant woman's biological age

October 16, 2017
Pregnant women who had low socioeconomic status during childhood and who have poor family social support appear to prematurely age on a cellular level, potentially raising the risk for complications, a new study has found.

Pregnancy history may be tied to Alzheimer's disease

July 18, 2018
A woman's history of pregnancy may affect her risk of Alzheimer's disease decades later, according to a study published in the July 18, 2018, online issue of Neurology, the medical journal of the American Academy of Neurology. ...

Thyroid dysfunction may lead to diabetes during pregnancy

June 7, 2018
Women with thyroid dysfunction in the first half of pregnancy face an increased risk for gestational diabetes, a form of diabetes that is typically diagnosed during the second trimester, according to a new study published ...

Offspring of older fathers may live longer: study

June 11, 2012
(Medical Xpress) -- If your father and grandfather waited until they were older before reproducing, you might experience life-extending benefits.

Certain medications for chronic inflammatory diseases appear safe during pregnancy

April 5, 2018
Anti-tumor necrosis factor medications (anti-TNFs) are effective in controlling chronic inflammatory diseases, but some physicians recommend that their patients discontinue them during pregnancy. In an Arthritis & Rheumatology ...

Recommended for you

Scientists grow functioning human neural networks in 3-D from stem cells

October 18, 2018
A team of Tufts University-led researchers has developed three-dimensional (3-D) human tissue culture models for the central nervous system that mimic structural and functional features of the brain and demonstrate neural ...

Functional engineered oesophagus could pave way for clinical trials 

October 18, 2018
The world's first functional oesophagus engineered from stem cells has been grown and successfully transplanted into mice, as part of a pioneering new study led by UCL.

New findings cast light on lymphatic system, key player in human health

October 16, 2018
Scientists at the Oklahoma Medical Research Foundation have broken new ground in understanding how the lymphatic system works, potentially opening the door for future therapies.

New model suggests cuffless, non-invasive blood pressure monitoring possible using pulse waves

October 16, 2018
A large team of researchers from several institutions in China and the U.S. has developed a model that suggests it should be possible to create a cuffless, non-invasive blood pressure monitor based on measuring pulse waves. ...

Age-related increase in estrogen may cause common men's hernia

October 16, 2018
An age-related increase in estrogen may be the culprit behind inguinal hernias, a condition common among elderly men that often requires corrective surgery, according to a Northwestern Medicine study was published Oct. 15 ...

Income and wealth affect the mental health of Australians, study shows

October 16, 2018
Australians who have higher incomes and greater wealth are more likely to experience better mental health throughout their lives, new research led by the Bankwest Curtin Economics Centre has found.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.