According to a new study, women who had their children at an older age have a better chance to live to an unusually old age.
The case-control study has been published online in the journal Menopause.
Researchers evaluated data from the Long Life Family Study, an international collaboration to review the genetics and familial components of exceptional survival, longevity, and healthy aging.
Three hundred eleven women who survived past the oldest fifth percentile of survival (according to birth cohort-matched life tables) were identified as cases, while 151 women who died at ages younger than the top fifth percentile of survival served as controls.
Looking at the cases of all 462 women, the study found a significant association for older maternal age — in which women had their last child beyond age 33 years — had twice the odds for survival to the top fifth percentile of survival for their birth cohorts compared with women who had their last child by age 29 years.
Several previous studies had observed a similar association. For example, an analysis of New England Centenarian Study cohort data revealed that women who gave birth to a child after age 40 years had four times greater odds for being a centenarian compared with women from the same birth cohort who had their last child at a younger age.
In this latest study, it was observed that having more children (identified as three or more) moderated the association between increased maternal age and later survival. Mortality was not assessed for women who had no children.
Study authors believe it is significant that numerous studies have documented the same relationship between older maternal age at birth and exceptional survival.
They believe these findings provide evidence for sustained reproductive fitness, with age as a selective force for genetic variants conducive to longer life.
“While this documented relationship is noteworthy, what is more meaningful is that these findings support the need to conduct additional studies that identify the various genetic influences on reproductive fitness, as these could also influence the rate of aging and a woman’s susceptibility to age-related diseases,” said Margery Gass, M.D.
The study will be published in the January 2015 print edition of Menopause.