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

This review article puts forward an intriguing and plausible evolutionary hypothesis: that during pregnancy, a significant endocrine, immune and metabolic remodelling of the maternal organism takes place, with processes associated with biological ageing that appear to accelerate throughout gestation but are partially reversed after birth. The review combines findings from human cohorts and various measurement platforms (epigenetic clocks, telomere length and clinical markers) to propose that a subsequent pregnancy, before full recovery from the first, may preserve the deficit and accumulate changes between pregnancies. Of course, it is critically important to distinguish between changes in the markers we use to estimate biological age and actual permanent ageing of the body. This hypothesis opens up interesting possibilities, but it has not yet been demonstrated that short pregnancies are responsible for the apparent effects of irreversibly aged cells, nor whether changes in structure necessarily lead to clinically significant long-term outcomes.

One limitation is that this is a review and constructs the conceptual framework based on previous studies—primarily observational ones—rather than an experimental study demonstrating causality. Although associations have been observed between intervals between pregnancies and certain obstetric and perinatal outcomes, it cannot be concluded that a short interval, on its own, causes an increase in biological age. Postpartum recovery and the biomarkers examined may be influenced by maternal age, body mass index, pre-existing conditions (particularly gestational diabetes), nutritional status, stress, the duration of sleep deprivation during breastfeeding, and socio-economic conditions.

Furthermore, epigenetic clocks and other indicators of biological age are also indirect measures. The differences may represent physiological or inflammatory changes, or variations in cellular composition during pregnancy that do not constitute irreversible damage. There is a lack of measurements that account for the time required for full recovery and whether incomplete recovery persists decades later, but this is acknowledged in the article itself.

They therefore provide a promising framework for guiding future research, but their results must be interpreted with caution. It is not a message that should be conveyed to women—that they will age more rapidly if pregnancies are too closely spaced—especially given our low birth rate. The key question is whether, in longitudinal studies, changes in these biomarkers would be sustained; which modifiers affect recovery and shape long-term maternal health; and what the actual implications of these markers are for mothers.