Reacción a "Pregnancies that follow one another in quick succession could accelerate the mother’s biological ageing, according to a study"

This timely review by Albright and Poganik published in Trends in Endocrinology & Metabolism synthesizes evidence from multiple longitudinal cohorts and biological aging measures to propose a novel, testable hypothesis: that long-term maternal biological aging trajectories may be influenced by the time available for postpartum recovery between pregnancies, rather than by the number of pregnancies.

Biological aging refers to the progressive accumulation of molecular, cellular, and physiological changes that impair bodily function and increase vulnerability to age-related diseases and mortality. Most commonly, this is measured via epigenetic age clocks, which are mathematical models based on patterns in DNA methylation. The review builds on a growing body of evidence showing that pregnancy is associated with accelerated epigenetic aging, followed by partial reversal postpartum. Specifically, interpregnancy interval, defined as the time between delivery and subsequent conception, is proposed as a missing variable to elucidate the biological burden of pregnancy on aging outcomes.

This article’s principal contribution is integrating these findings with epidemiological evidence on pregnancy spacing, parity, and maternal health. However, the evidence supporting the proposed recovery-window hypothesis remains preliminary. Although longitudinal findings suggest that subsequent pregnancies may interrupt biological age recovery, studies have not established that shorter interpregnancy intervals cause persistent acceleration of biological aging or increase long-term mortality through this mechanism. Most existing research is largely observational, some key studies have relatively small samples, and findings may be influenced by maternal age, socioeconomic circumstances, breastfeeding, body mass index, psychosocial stress, and other factors.

There is an important distinction between the relatively well-supported observation that markers of biological age change during pregnancy and postpartum, versus the still-untested hypothesis that insufficient recovery between pregnancies causes cumulative, lasting biological aging. Importantly, epigenetic clocks and other biological age measures are indirect biomarkers, developed in nonpregnant populations, thus, pregnancy-related changes may reflect normal, adaptive physiological remodeling rather than accumulated cellular damage or irreversible aging. The findings therefore should not be reported as demonstrating that pregnancy permanently ages women, that closely spaced pregnancies necessarily accelerate aging, or that a particular interpregnancy interval prevents biological aging. Rather, this review provides a compelling framework for future longitudinal research examining whether postpartum recovery trajectories predict subsequent health and whether modifiable factors can improve maternal recovery.