(NewsNation) — Pregnancy may accelerate biological aging in women who have never given birth by up to 5.3 years, according to a new study.
Researchers also found that an older first-trimester epigenetic age, a measure of biological rather than chronological age, was associated with a range of pregnancy complications, although chronological age was not.
“Biological aging may serve as a useful metric to objectively measure how pregnancy can serve as a window to future health,” the study’s lead author, Dr. Danielle Panelli, told Medscape Medical News. “People who develop gestational diabetes and hypertensive disorders can be at increased risk for these health conditions later in life.”
Rising risks in older mothers
Maternal mortality rates in the U.S. exceed those in other high-income countries, a trend worsened by a rise in pregnancies among women over 40. One study noted a 194% increase in births to older mothers since 1989.
While older age is a known risk factor for complications, the latest study, published in Obstetrics & Gynecology, suggests chronological age alone is not a reliable predictor.
“Some older women have uncomplicated pregnancies, and younger women can have unexpected complications,” the study said.
Study findings
Researchers screened 305 women, enrolling 75 nulliparous women aged 18 to 50 seeking obstetric (10-14 weeks pregnant) or gynecologic care between 2020 and 2021. Of the cohort, 45 women were pregnant, and 61 completed the study.
Blood samples were collected at enrollment and again postpartum — day 1 for pregnant women or 7 months for nonpregnant women — to measure epigenetic age using 11 molecular clocks.
Pregnant women showed significant acceleration in biological aging across six of the 11 epigenetic clocks compared with nonpregnant women.
Researchers also found that first-trimester epigenetic age correlated with immune-mediated pregnancy complications, including hypertensive disorders, gestational diabetes, preterm birth, and small-for-gestational-age babies, even after adjusting for age and BMI.
“The most interesting part about epigenetic age, or any type of biological age, is that, unlike chronological age, it is modifiable,” Panelli said. “Ideally, translating this to clinical practice would mean that if you knew someone had accelerated epigenetic age early in pregnancy, you could initiate lifestyle interventions earlier, before they potentially go on to develop complications.”
Why epigenetic age matters
Epigenetics can also mark accurate chronological time versus biological time, according to the National Institute of Aging.
“Our chronological age is based on our birthdate, but biological age means the true age that our cells, tissues, and organ systems appear to be, based on biochemistry,” the institute said.
A person’s epigenome is affected by environment and experience over time — “similar to how rings on the inside of a tree can tell us the tree’s age and mark where it had encountered damage or stress.”