Pregnancy Ages Women Faster, But Postpartum May Reverse It

“Tatanda ako nang maaga sa inyo.”

It’s a line we have heard from our mothers, and perhaps something we utter these days whenever our patience is running thin thanks to our child’s antics. Well it seems that there’s a grain of truth in it. Two studies from the US have found that while motherhood can be a profound and life-changing experience, it also comes with significant biological costs.

One study from the Columbia University Mailman School of Public Health, titled, “Pregnancy Accelerates Biological Aging In Healthy Young Adults,” found that pregnancy can indeed accelerate biological aging in women, exploring how pregnancy influences aging on a cellular level, potentially impacting long-term health.

Aging in mothers

The Columbia study focused on a cohort of 1,735 young Filipino adults to compare biological aging markers of women who had pregnancies to those who had not. And researchers have found that each pregnancy can add two to three months to a woman’s biological aging process. No similar effect has been found on men, which could indicate a unique link between pregnancy and accelerated aging in women.

Biological aging is different from chronological aging, with the former referring to the functional and molecular changes that occur in an individual’s cells over time. These changes can then be measured with the use of various “biomarkers” which are collectively known as “epigenetic clocks.” These clocks can then estimate an individual’s biological age based on cellular function and health, which can provide insights into an individual’s health beyond their actual age.

Lead author Calen Ryan, PhD, from the Columbia Aging Center emphasized the significance of these finding, saying, “Epigenetic clocks have revolutionized how we study biological aging across the life-course and open up new opportunities to study how and when long-term health costs of reproduction and other life events take hold.”

Epigenetic clocks and pregnancy

The study used advanced tools that measure DNA methylation, allowing researchers to assess the impact of pregnancy on biological aging in young women. This approach fills the critical gap in understanding how reproductive history influences health outcomes from an early age. The researchers found that for each additional pregnancy, there was an increase of over two months in biological age, a pattern that remained consistent even after adjusting for factors such as socioeconomic status, smoking, and genes.

“Our findings suggest that pregnancy speeds up biological aging, and that these effects are apparent in young, high-fertility women,” noted Ryan. “Our results are the first to follow the same women through time, linking changes in each woman’s pregnancy number to changes in her biological age.”

Other factors

On the other hand, the study highlights the importance of context. Many pregnancies in the study’s baseline measure occurred during late adolescence, a critical period when women are still growing. This overlap between maternal and personal development may amplify the biological costs of pregnancy, especially in areas with limited access to healthcare and resources.

“Many of the reported pregnancies in our baseline measure occurred during late adolescence when women are still growing. We expect this kind of pregnancy to be particularly challenging for a growing mother, especially if her access to health care, resources, or other forms of support is limited,” Ryan explains.

Ryan also cautions that the aging process can vary across different cultural and geographical contexts. The study’s main subjects are Filipinos, while the current understanding of epigenetic aging is largely based on studies in Northern America and Europe, hence it may not fully capture the differences of aging in other regions.

“Our current understanding of epigenetic clocks and how they predict health and mortality comes largely from North America and Europe, and the aging process can take slightly different forms in the Philippines and other places around the world,” Ryan notes.

Ryan acknowledges the need for further research: “We still have a lot to learn about the role of pregnancy and other aspects of reproduction in the aging process. We also do not know the extent to which accelerated epigenetic aging in these particular individuals will manifest as poor health or mortality decades later in life.”

Yes, mothers age, but there’s postpartum rejuvenation

Another research, this time from the Yale School of Medicine seems to differ with Columbia’s findings. The study, led by Kieran O’ Donnell, PhD, explores how pregnancy initially accelerates aging but also reveals a significant reversal in the postpartum period.

Yale also examined a unique pregnancy cohort with epigenetic data collected throughout pregnancy. The researchers found that from early to late pregnancy–a period of around 20 weeks–biological age increased by about two years. This confirmed that pregnancy accelerates aging, consistent with Columbia’s findings.

However, Yale discovered something else. O’Donnell said, “At three months postpartum, we saw a remarkably large decrease in biological age, by as much as eight years for some individuals, so while pregnancy increases biological age there is a clear (and pronounced) recovery in postpartum.”

This means that the study found that biological age also decreased significantly three months postpartum, suggesting a strong recovery effect. Moreover, this decrease seems to be more evident among women who breastfed, while women who had a higher pre-pregnancy body mass index (BMI) experienced less pronounced recovery. Hence, indicating that postpartum recovery may be influenced by maternal health and breastfeeding practices.

O’Donnell highlights the implications of these findings: “First, we don’t know if the postpartum recovery effect is relevant for short or long-term maternal health outcomes and if these effects can accumulate over successive pregnancies. Likewise, we don’t know if postpartum decrease in biological age is simply the system recovering to pre-pregnancy biological age or, more provocatively, if pregnancy may have a rejuvenating effect.”

What does this mean for mothers

Both studies provide sufficient evidence that pregnancy affects biological aging, but their findings differ on the impact and duration of this effect. Columbia’s research indicates that each pregnancy accelerates biological aging, while Yale’s study suggests that this acceleration may be temporary, with a significant recovery observed postpartum.

Ultimately, these findings highlight the importance of comprehensive healthcare for women before, during, and after pregnancy. Supporting young mothers with adequate healthcare, resources, and social support is crucial to offset the potential long-term impacts of accelerated biological aging. Moreover, recognizing the role of maternal health factors, such as pre-pregnancy BMI and breastfeeding, can help mothers and professionals in coming up with interventions to enhance postpartum recovery.

Read here for a mom’s postpartum recovery kit essentials.