A study found that women able to give birth after the age 33 often live longer. Researchers say this is not a reason to postpone giving birth and stress that the findings are based on certain women's natural ability to give birth later in life.

The study looked at biopsychosocial and genetic data collected from 551 families with members living to very old ages. Researchers took the ages of 462 women's last childbirths and how long each woman lived. Those whose last childbirth occurred after the age of 33 had the twice the probability of living to age 95, or older, when compared with women whose last birth occurred by age 29.

The data was collected as part of the Long Life Family Study (LLFS) and analyzed at the Boston University School of Medicine (BUSM). The findings were published in Menopause: The Journal of the North American Menopause Society.

In addition to the longevity findings, researchers also obtained evidence that women may be the evolutionary drivers of slow aging. In other words, women may possess more genetic variants for longer life spans than men.

"If a woman has those variants, she is able to reproduce and bear children for a longer period of time, increasing her chances of passing down those genes to the next generation," said Thomas Perls, co-author of the study, head investigator of the LLFS and medical professor at BUSM.

This study lends support to previous research done on the association between a mother's age and her probability of living a long time. The New England Centenarian Study, in particular, reported that women who had a baby after turning 40 were four times more likely to live to 100.

The basic idea behind this research is that if a woman's reproductive system ages at a rate slower than average, giving her the ability to safely have children at an older age, then it seem likely that the rest of her body is aging at a slower than average rate as well.

The BUSM study is one of many attempting to understand how genetics affect aging and age-related diseases.