Dr Laurence Shaw, will tell the 22nd annual conference of the European Society of Human Reproduction and Embryology, that it is only in the past 150 years or so that better hygiene, living conditions and medical advances have made it relatively common for people to live into their 60s, 70s, 80s and sometimes beyond. Before that time men and women would have been more likely to die around the age of 50. For women this often meant they died at or before their menopause.
Dr Shaw, deputy medical director, at the Bridge Centre, London, UK, will say: "Homo sapiens has existed for 150,000 years and for all of that time until about 100 to 150 years ago, women had their babies when they were in their late teens and early twenties when their fertility was at its peak. In the subsequent 20 to 30 years, they raised their children, and their declining fertility meant that they were less likely to have further children of their own and could help their daughters to tend their own babies. Most women died before they reached menopause or shortly after.
"Therefore, the accelerated decline in fertility, rather than the menopause itself, is the evolutionary adaptation that has occurred in the human line over the past 2.8 million years, and, until the last 150 years, the postmenopausal state and the prior decline in fertility was positively useful. Living through the menopause and beyond is not a part of our natural life.
"Our improved longevity and other aspects of industrialised society have some incompatibilities with this evolutionary strategy. In particular, there are three serious issues: