Mothers of the Future May be Older... Much Older
Until now, freezing of unfertilized eggs has been a trickier process than freezing of sperm or embryos. But techniques such as Cryotop will provide new options to women who want to preserve their eggs for later fertilization.
The entire process of in vitro fertilization (IVF) adds a new wrinkle to the birth process, and the differences between our physiology and modern society. IVF is popular because women increasingly want to delay childbirth until they are financially stable and otherwise in a good position to start a family. Yet this might not occur until relatively late in life -- and with increasing lifespans, women might choose to wait to have children until their 50s, 60s or even later.
This, of course, conflicts with the way that the human body has evolved over the last 150,000 years. Until about 100 years ago, women's peak childbearing years were in their teens and early 20s; after that, with lowered fertility, they could help their daughters raise their children, and relatively few women lived long past menopause. Therefore, infertility had a social benefit, and post-menopause was a rare and unnatural condition.
Today, we discourage teen girls and young women from having children, urging them to focus on their educations and other aspects of life. Meanwhile, women in their 50s may have 40 or 50 healthy years ahead of them -- years that they might want to devote to parenthood.
As our notions of aging and childbirth change, so will our expected timeline for starting a family. Some futurists believe that people might have multiple families at different times in their lives, while others believe that people's youth (teen years through their 30s) will be devoted to self-fulfillment, with marriage and childbirth reserved for what we today consider to be "midlife."