More children, shorter lifespan? Clear evidence from the Great Finnish Famine

Scientific theory predicts that having more offspring leads to a shorter life span, including in humans. However, despite some hundred years of research, there is no unequivocal evidence for this link.

Researchers from the University of Groningen (the Netherlands), the University of Exeter (UK), and the University of Turku (Finland) have now shown that under harsh conditions, the biological cost of reproduction can indeed shorten women’s lifespans. The results are published in Science Advances.

In the 1860s, Finland experienced several harsh winters, resulting in a series of poor harvests and famine. Researcher Euan Young from the University of Groningen used life-history data from Finnish parish records to study the effects of these harsh conditions on the relationship between reproductive effort and lifespan.

In total, Young studied data from 4,684 women over a period of 250 years. Women who were exposed to the famine during their reproductive years (19–45 years old) lived shorter lives when they had had more children. Mothers with just one child on average reached the age of 71.6 years, while a mother with 15 children reached the age of 64.3 years. So, each child shortened the mother’s lifespan by about half a year. Women who were not exposed to the famine, or who experienced it during a different phase of life, did not experience a shorter lifespan.

Young says, “For over a hundred years, researchers have studied how reproduction influences lifespan, with mixed results. This has led some to believe that reproductive behavior is not a significant factor in shaping human aging. Contrary to this, our findings suggest that under harsh conditions, reproductive effort certainly affects lifespan.”