The timing of key reproductive milestones in women—such as the onset of puberty and age at childbirth—may have far-reaching consequences on long-term health. A new study conducted by researchers at the Buck Institute for Research on Aging, USA, reveals that girls who experience puberty before age 11 or women who give birth before age 21 face significantly higher risks of chronic diseases later in life.

According to the findings, these women are twice as likely to develop Type 2 diabetes, heart failure, and obesity, and up to four times more likely to suffer from severe metabolic disorders compared to women who experience puberty or childbirth later. The research suggests that while early reproductive capacity may benefit survival of offspring, it carries substantial costs for women’s health and longevity.

Genetic links to ageing and lifespan

The study, published in the journal eLife, highlights that reproductive timing is genetically associated with ageing processes. Women who undergo later puberty and later childbirth tend to have a longer lifespan, lower frailty, slower epigenetic ageing, and reduced risk of diseases such as Type 2 diabetes and Alzheimer’s.

Lead researcher Professor Pankaj Kapahi explained: “Genetic factors that favour early reproduction come with a significant cost later in life, including accelerated ageing and disease. It makes sense that the very factors that enhance offspring survival may result in detrimental consequences for the mother.”

Large-scale analysis and genetic markers

To reach these conclusions, scientists conducted regression analysis on data from nearly 200,000 women in the UK. The research identified 126 genetic markers linked to the effects of early puberty and childbirth on ageing and disease risk. One of the critical mediators identified was Body Mass Index (BMI).

Kapahi noted that early reproductive events tend to contribute to a higher BMI, which increases the likelihood of obesity and metabolic disorders. “One can envision that enhancing the ability to absorb nutrients benefits the offspring. But if nutrients are plentiful, it can raise the risk of obesity and diabetes,” he said.

Implications for public health

The findings carry important implications for public health and women’s preventive care. Since early puberty and early childbirth are now more frequently observed across the globe, awareness about their long-term consequences becomes vital.

Kapahi emphasized: “These risk factors, whether positive or negative, clearly influence a variety of age-related diseases and should be considered in the larger context of overall health.”

The researchers argue that understanding the long-term health impact of reproductive timing can pave the way for personalised healthcare strategies. Preventive approaches could include lifestyle modifications, regular metabolic screenings, and tailored dietary recommendations to mitigate future risks for women who experience early reproductive milestones.

Looking ahead

As science continues to uncover the interplay between reproduction and ageing, this study underscores the importance of early interventions. By identifying women at risk and providing them with personalised care strategies, healthcare systems can work to reduce the burden of age-related illnesses and improve overall quality of life.

Ultimately, the research reinforces a powerful idea: the biological clock doesn’t just govern fertility, but may also shape the trajectory of ageing and long-term health.