Older first-time mothers may live longer: Study

The researchers found an association between a woman's age at childbirth and parity -- the number of times a woman has been pregnant -- with survival to age 90.

"We found that women who had their first child at age 25 or older were more likely to live to age 90," said lead author Aladdin Shadyab from University of California-San Diego, US.

The findings indicate that women with two to four term pregnancies compared with a single term pregnancy were also more likely to live at least nine decades, Shadyab added.

Women who lived to age 90 were also more likely to be college graduates, married, have a higher income and less likely to be obese or have a history of chronic disease, the researchers said.

However, "our findings do not suggest that women should delay having a child, as the risk of obstetric complications, including gestational diabetes and hypertension, is higher with older maternal ages," Shadyab noted.

Surviving a pregnancy at an older age may be an indicator of good overall health, and as a result, a higher likelihood of longevity.

"It is also possible that women who were older when they had their first child were of a higher social and economic status, and therefore, were more likely to live longer," Shadyab added.

In the study, published online in American Journal of Public Health, the researchers hoped that the study may help identify targets for future interventions among women in the preconception and family planning phases of their lives, which may improve women's healthy longevity in the long term.