Men's desire for progeny a factor in menopause? Maybe, maybe not

HAMILTON, Ontario, June 14 (UPI) -- Man's desire for younger women may be a factor in women's reproductive development, a/k/a menopause, researchers at McMaster University in Ontario said.

Researchers said menopause is an unintended consequence of human evolution caused by natural selection and by men's preference for younger women as romantic partners, Healthline reported Thursday.

"In a sense it is like aging, but it is different because it is an all-or-nothing process that has been accelerated because of preferential mating," said Rama Singh, a biology professor at McMaster. "Menopause is believed to be unique to humans, but no one has yet been able to offer a satisfactory explanation for why it occurs."

The theory is that older women stop producing estrogen and become infertile because men prefer mating with younger women capable of bearing healthier children.

There are skeptics, Healthline said.

"I know we like to blame men for a lot of things, but I don't think this can be one of them," Dr. Rebecca Brightman, a clinical instructor of Obstetrics, Gynecology and Reproductive Science at the Icahn School of Medicine at Mount Sinai Hospital in New York, said in an interview with Healthline. She was not involved in the study.

Brightman notes pregnancy can be hard on a woman's body and there may be an "evolutionary advantage to being incapable of having children later in life. Mothers want to be around to care for their children."

The Canadian scientists used computer modeling and computer simulations to help develop their hypothesis and conclusion. Testing different theories, they learned a man's mating preference for younger women would explain the genetic mutations resulting in menopause.

By better understanding the biological function of menopause, Singh said it could be reversed some day since it isn't innately part of a woman's reproductive cycle.

"How do you evolve infertility? It is contrary to the whole notion of natural selection," Singh said. "Natural selection selects for fertility, for reproduction -- not for stopping it."