Amy Klein in Aeon:
For a woman over 42, there’s only a 3.9 per cent chance that a live birth will result from an IVF cycle using her own, fresh eggs, according to the American Society of Reproductive Medicine (ASRM). A woman over 44 has just a 1.8 per cent chance of a live birth under the same scenario, according to the US National Center for Chronic Disease Prevention and Health Promotion. Women using fresh donor eggs have about a 56.6 per cent chance of success per round for all ages. Indeed, according to research from the Fertility Authority in New York, 51 per cent of women aged between 35 and 40 wait a year or more before consulting a specialist, in hopes of conceiving naturally first. ‘It’s ironic, considering that the wait of two years will coincide with diminished fertility,’ the group says. Stories of celebrities and other older women having babies have led to misunderstanding precisely because they fly in the face of long-held beliefs: for many years, all women heard was that fertility takes a dive at 30-35. But when you see plenty of people having no trouble having babies until 40, you think it’s just a scare tactic. That’s what happened to me, anyway. Raised in a traditional Jewish, family-oriented community that emphasises early marriage and plenty of children, I was constantly warned about waiting too long to get married and have kids. But when I left that community, I saw so many women who had kids at 37, 38, that I thought it was all bubbe meises, old wives’ tales.
It’s not. There is a declining rate of fertility strongly tied to age – but the exact numbers have recently come up for debate. In a piece for The Atlantic in 2013 headlined ‘How Long Can you Wait to Have a Baby’, the psychologist Jean Twenge showed that much of the research cited by articles and studies (such as how one in three women aged 35-39 will not be pregnant after a year of trying) was based on ancient figures, such as French birth records from 1670 to 1830. She also cites a 2004 Obstetrics and Gynecology study examining chances of pregnancy among 782 European women. With sex at least twice a week, the study found, 82 per cent of 35-to-39-year-old women conceived within a year, compared with 86 per cent of 27-to-34-year-olds.