A recent study conducted by researchers from the University of Helsinki and the Minerva Foundation Institute for Medical Research indicates that women’s reproductive history significantly influences both lifespan and biological aging. The research, which included data from nearly 15,000 participants in a twin study that began in 1975, reveals that factors such as family size and the timing of childbirth are closely linked to women’s health outcomes and longevity.
The findings show that women who have two to three children tend to enjoy the longest lifespans. In contrast, those who either have many children—defined as more than four—or remain childless appear to experience accelerated biological aging. According to the study, pregnancies occurring between the ages of 24 and 38 are associated with more favorable aging patterns.
Mikaela Hukkanen, a doctoral researcher involved in the study, explains the implications of these findings within the framework of evolutionary biology. “From an evolutionary perspective, organisms have limited resources such as time and energy. When a large amount of energy is devoted to reproduction, it detracts from bodily maintenance and repair mechanisms, potentially shortening lifespan,” she stated.
Unexpectedly, the research also found that women without children exhibited signs of faster biological aging compared to those with a modest number of children. This anomaly may stem from various lifestyle or health-related factors that were not fully accounted for in the analysis.
The research team stresses that these findings apply at a population level and do not establish definitive cause-and-effect relationships. As highlighted by study lead Dr. Miina Ollikainen, individual choices regarding family size should not be altered based solely on this research. “Family size has decreased, and the age of first childbirth has increased since the time period covered by our study,” she remarked, underscoring the need for personal agency in reproductive decisions.
Biological Aging Measured via Epigenetics
An innovative aspect of this study was the biological measurement of aging. Researchers determined epigenetic clocks from blood samples of over 1,000 participants. These clocks assess biological aging by evaluating the gradual deterioration of cells and tissues, providing insight into age-related changes that can manifest years before death.
The results corroborate previous mortality data, indicating that women with either many children or none at all are biologically older than their chronological age. “A person who is biologically older than their calendar age faces a higher risk of death,” explained Dr. Miina Ollikainen. “Our results illustrate how life history choices leave a lasting biological imprint measurable long before old age.”
The study also indicates that early childbirth may relate to biological aging, presenting a complex interplay of reproductive timing and health outcomes.
Published in Nature Communications, these findings contribute to the ongoing discourse on the evolutionary trade-offs between reproduction and lifespan. The research emphasizes that while historical data provides valuable insights, individual circumstances vary widely, and personal reproductive choices should reflect one’s own situation and preferences rather than statistical trends.
Overall, this comprehensive study sheds light on the intricate relationship between reproductive history and health, suggesting that women’s choices significantly impact their biological aging and longevity.
