Study by SFU health sciences researchers finds association between the number of children women have and cellular aging

A study by SFU health sciences researchers shows that the number of children born to a group of Mayan women is associated with the rate at which their bodies' cells age.

Health sciences professor Pablo Nepomnaschy and postdoctoral researcher Cindy Barha examined rural populations of Guatemalan women who exhibited cellular signs of longevity.

Their findings contradict a previous theory that the lengths of telomeres shorten as children age, and that bearing children robs mothers of cellular energy.

Telomeres are the protective tips found at the end of each DNA strand, and indicate cellular aging. Longer telomeres are integral to cell replication and are associated with longevity. The study-group women with longer telomeres had more children.

Pablo says the findings contradict life-history theory, which predicts that producing more offspring accelerates biological aging.

“The slower pace of telomere shortening found in the study participants who have more children, however, may be attributed to the dramatic increase in estrogen, a hormone produced during pregnancy,” he says.

“Estrogen functions as a potent antioxidant that protects cells against telomere shortening.”

Another reason for longer telomeres in women with more children may be found in the social systems of mothers’ communities.

"They receive more social support from their relatives and friends,” says Pablo.

“Greater support leads to an increase in the amount of metabolic energy that can be allocated to tissue maintenance, thereby slowing down the process of aging.”

However, the researchers emphasize aging is a complex process and we still have much to learn.