Scientists Explore Whether Pregnancy Leaves Lasting Changes in Biological Age

Could having pregnancies too close together affect how quickly a woman's body ages? A new scientific review suggests that pregnancy temporarily accelerates biological aging, while recovery after childbirth may help reverse some of these changes. Researchers are now exploring whether insufficient recovery between pregnancies could contribute to long-term maternal health risks.

Published in Trends in Endocrinology & Metabolism, the review examined existing evidence linking pregnancy, postpartum recovery, biological aging and the interval between successive pregnancies.

Unlike chronological age, biological age reflects changes in the body's cells and physiological systems that may indicate how rapidly aging-related processes are occurring.

Researchers found that biological age, measured using molecular markers such as epigenetic clocks, generally increases during pregnancy before declining at least partially after childbirth.

However, whether these pregnancy-related changes disappear completely remains uncertain.

Importantly, researchers proposed a concept called the recovery period hypothesis, suggesting that becoming pregnant again before the body has sufficiently recovered could allow aging-related changes to accumulate across pregnancies.

Supporting this possibility, a longitudinal study involving 130 women found that those who became pregnant again during nearly four years of postpartum follow-up showed disruptions in the expected slowing of biological aging.

The review also highlighted evidence linking shorter intervals between pregnancies with adverse maternal and infant outcomes.

A meta-analysis involving nearly 47 million pregnancies found that intervals of 18–23 months were associated with the most favourable perinatal outcomes, while intervals shorter than six months showed greater risks.

Researchers suggested that hormonal changes, inflammation, oxidative stress, breastfeeding and maternal metabolic health may influence biological aging and postpartum recovery.

However, they emphasised that existing evidence does not establish that closely spaced pregnancies directly cause permanent biological aging.

Larger, long-term studies are needed to determine how completely biological age recovers after childbirth and whether pregnancy spacing influences aging-related health risks later in life.

REFERENCE: Albright S, Poganik J. (2026). The postpartum recovery window as a determinant of maternal aging. Trends in Endocrinology & Metabolism. DOI: 10.1016/j.tem.2026.09.002