As a woman, you do become less fertile as you get older, eventually culminating in menopause and the end of your potential babymaking years. But what does "less fertile" mean, and at what age, and how quickly does the drop-off in fertility happen?
According to this really fascinating piece by Jean Twenge at The Atlantic, some of the commonly cited scare stats — that one in three women ages 35 to 39 will not be pregnant after a year of trying, say — are based on extremely old data collected from historical birth records that don't necessarily reflect what's happening with real women who are alive right now. That statistic mentioned above, for instance, comes from French records (likely those collected by local church baptismal registries) for the years 1670 to 1830.
That matters because fertility is affected by things like quality of nutrition, infection rates, and even childhood illnesses — all of which have changed drastically for the average Western woman since the 19th century.
Look at more modern records, and the outlook for post-30 babymaking is completely different. Read the rest