A trawl through thousands of church records in Finland dating to the 17th and 18th centuries has found a correlation between the age at which a woman had her first child, the number of children she had, and the age at which she died.
The scientists behind the study - one of the biggest on pre-industrial society - believe the findings indicate that women who delay starting a family and have fewer children may have a natural tendency to live longer than women who become mothers at a young age.
Jenni Pettay and colleagues at Turku University investigated four generations of Finns who lived before the industrial revolution and modern contraception. They analysed several traits - such as age at childbirth and longevity - with a statistical method normally used for wild animal populations.
In Proceedings of the National Academy of Sciences, the researchers wrote: "We found strong ... correlations ... suggesting reduced life spans in females who either started to breed relatively early or who then bred frequently."
No trade-off in longevity was found for fatherhood.Reuse content