Friday, May 20, 2005

Another Study You Won't Hear About Around Valentine's Day

Later Moms, Longer Lives

Waiting to have children may add years to a woman’s life, says Jenni Pettay of the University of Turku in Finland. The evolutionary biologist analyzed 5,000 birth records from four generations of 17th- and 18th-century Finns and found that women who waited the longest before having their first child were statistically more likely to live longer. The delay in childbirth seems to be inherited: Late mothers’ daughters also tended to become late mothers themselves. (Late was defined as after 30.)

Previous research has suggested that women who delay having children live longer. But none of these studies was able to determine if the longevity was due to cultural factors, such as a higher socioeconomic class or better living conditions. Pettay got around those issues by studying women from a homogeneous population who did not have access to contraception or advanced medical care.

Still, Pettay says, it’s culture, not genes, that explains why Westerners delay parenthood: “In modern society there tends to be a low number of offspring per couple, so natural selection isn’t at work. But this study does suggest there may be benefits to later motherhood that evolved to counteract the decrease in total fertility years, such as living longer to provide care to grandchildren.”

—Jocelyn Selim

2 comments so far. What are your thoughts?

Anonymous said...

The Finns can do this because they've got some fantastic records, reasonably low immigration and a fairly stable population. But the big problem here is that the 17th century . & the 18th C. is not a particularly good proxy for now, give the health care situation. There are many, many things an older woman would know in the 1700's that younger woman may not have been instructed in at all. They were expected to learn this via trial and error. (Very few females would have been educated, those who were in the most rudimentary manner via grade school knowledge at best). An older woman would have a lifetime of observations and experience behind her to enable her keep herself & her child healthy.

Delayed parenthood and smaller family size have been the hallmarks or the western and urban experience for over 500 years. It is a marked difference from many other cultures, and over time does tend to favor the education and more favorable consideration of & for women.

Still it's an interesting study for what it does tell us about history. Education matters, and experience matters more than 'blooming youth' at this very early demographic juncture. Consider though that it was highly unlikely the mothers would live much beyond 20 years after the birth of this first child too.  

Posted by VJ

Anonymous said...

Geez, Written too fast due to time constraints:

That should be 'given the health care situation'.

And 'Delayed parenthood and smaller family size have been the hallmarks OF the western and urban experience for over 500 years.'

And mark me down as saying that our legal traditon eventually got around to consideration of women's rights, while some parts of the world still bask in the reflected glory of what was the 8th Century in that regard. That helped later child birth and smaller family sizes too, but it too a very long time to kick in effectively.  

Posted by VJ