The Risks of Reproductive Impairment in the Later Years of Childbearing

A notable feature of the present baby bust in the United States is that substantial proportions of women are delaying much of their childbearing until relatively late in their reproductive lives. One concern about this delayed childbearing is that many women may end up either childless or with fewer children than they desire, owing to reproductive impairment. This paper reviews evidence concerning the decline of reproductive ability with age. The findings can be distilled into two main facts. First, the proportion of women with low reproductive ability increases steadily from age 15 to age 50. Second, this rise is moderate until the mid-30s when it begins to increase mores harply. While the current consensus is that most healthy women in their late thirties have a good prospect of giving birth to a healthy infant, a substantial minority of postponers will end up childless or with fewer children than they desire, due to reproductive impairment as well as to social causes.