Question: why are people over a certain age not able to have children

Sam Tazzyman answered on 16 Jun 2011:

Quite often men can continue to have children even when they get quite old. But when they get to a certain age, women go through something called the “menopause”, which is a variety of physical changes that mean that they can no longer have children. Why this happens is something scientists are still trying to figure out for sure, but they think it might be because of something called the “grandmother effect”. This is the idea that after a certain age, its evolutionarily better for women to help look after their grandchildren than to have more children themselves. But it’s still being tested – it’s quite hard to get good information about how much of an effect grandmothers have on a grandchild’s chances of surviving.