It's widely acknowledged that pregnancy imposes significant physiological stress on a woman's body, making it a natural challenge. Previous research has indicated that pregnancy can have profound effects, potentially hastening the aging process.
On March 22nd, Assistant Professor Kieran O’Donnell from the Yale School of Medicine published the latest findings in Cell Metabolism, confirming that indeed, pregnancy does accelerate aging. However, the study also revealed a substantial reversal of this aging effect within three months postpartum.
"While it's not surprising that pregnancy incurs losses, the extent of this reversal is somewhat unexpected," remarked O’Donnell.
Source: Chicago Tribune
DNA methylation is a chemical modification of DNA that can influence gene expression activity without altering the gene sequence, known as epigenetics. Levels of DNA methylation increase gradually during the aging process, reflecting the physiological stresses accumulated by the body over time. Researchers have developed various epigenetic clocks to assess a person's biological age based on DNA methylation levels. Some studies have found that biological age is a better predictor of health issues such as cardiovascular disease and dementia than a person's chronological age.
Previously, Vadim Gladyshev, a biomedical scientist at Harvard Medical School, stated, "Unlike age arranged in chronological order, biological age is very flexible, it's a fluid parameter that can fluctuate up and down." Last year, his team published a study in Cell Metabolism indicating a decrease in biological age in mice during pregnancy, suggesting a similar effect may occur in humans. The cessation of several stress conditions also reversed biological age.
O’Donnell's research confirms Gladyshev's team's findings. The study found a significant positive correlation between pregnancy status and stage and biological age, with an increase of approximately 2 years in maternal biological age within just 18 weeks from early to late pregnancy. However, three months postpartum, there was a significant reversal in maternal biological age, with a reversal magnitude of 2 to 3 times the increase in biological age from early to late pregnancy.
The research also found that not everyone experiences the same degree of recovery postpartum. Individuals who were overweight before pregnancy showed lower levels of biological age recovery postpartum, with significantly less recovery in biological age at three months compared to those of normal weight.
It is worth mentioning that the researchers also analyzed the relationship between breastfeeding and accelerated aging during pregnancy. Compared to formula feeding or mixed feeding, individuals who exclusively breastfed showed the highest degree of postpartum biological age recovery.
However, O’Donnell stated, "We did not measure participants' biological age before pregnancy, so we cannot claim this is a fountain of youth effect. But these data are insightful, and I hope to continue following up on this research in the future."
Related Paper: https://doi.org/10.1016/j.cmet.2024.02.016
