Clearly measurable

Pregnant women age by two years in just a few weeks

According to a new study, pregnancy makes you old - at least temporarily.(Bild: stock.adobe.com - Malambo C/peopleimages.com)

A phenomenon that many have already suspected has now been confirmed by a recent study: pregnancy accelerates biological ageing. After birth, however, there is a surprising effect.

In just twenty weeks, pregnant women age by up to two years, write experts from the US Yale School of Medicine in their study in the journal "Cell Metabolism". In general, women's bodies undergo extensive changes: the growing foetus causes organs to shift, pelvic joints become looser and pregnancy hormones change appetite and energy levels. In addition, some neurons in the brain are permanently rewired.

Aneffect otherwise only known from alcohol, nicotine and stress
Biological age can differ significantly from chronological age, as it is determined by genes and external influences, including lifestyle. The best-known factors for premature ageing are an unhealthy diet, alcohol, nicotine and stress.

The team led by perinatal researcher Kieran O'Donnell and biostatistician Hung Pham has now analyzed blood samples from 119 women at various times during and after pregnancy. They confirmed the results of a study from the previous year: they found that the stress of pregnancy accelerates ageing.

Big surprise after birth
They concentrated on so-called DNA methylations. These are tiny chemical modifications of the genetic material that - unlike DNA itself - can change over the course of a lifetime. These methylations form certain patterns that researchers can use to estimate a person's biological age - carrying a baby to term produces some similar patterns that can also be observed in older people.

The big surprise, however, was the values after birth: "Three months later, we observed a remarkable decrease in biological age, in some people by as much as eight years," explains O'Donnell. After pregnancy, the body recovers in record time, so to speak.

Healthy lifestyle also beneficial here
However, this does not happen equally quickly for all women - the lifestyle before pregnancy also plays a major role here, specifically through the body mass index. Women who were overweight before giving birth did not recover their biological age as quickly. In contrast, breastfeeding led to a greater decline in maternal biological age within three months of giving birth.

Still two big unknowns
According to O'Donnell, these observations offer interesting new impulses for ageing research - although there are a few things to consider: it is not clear whether the recovery effect after birth is relevant for the short- or long-term health outcomes of mothers, and whether these effects accumulate over several successive pregnancies.

And O'Donnell mentions a second unknown: "Similarly, we don't know whether the reduction in biological age after childbirth is simply due to the system recovering to pre-pregnancy biological age or, more provocatively, whether pregnancy has a rejuvenating effect."