Fertility naturally declines as women age. But in Japan, child adoption is not a popular solutions to infertility, even for older women--unlike the situation in the United States. We investigate whether knowledge of age-related female fertility (i.e., that the pregnancy rate of women in their 40s is lower than that of women in their 30s) is related to individuals’ subjective probability of having a child. Among women in their early 40s and married men with wives in this age group who do not yet have children, the subjective probabilities of having children are approximately 10% higher among those with incorrect fertility knowledge than among those with correct fertility knowledge. The results suggest that increasing the accuracy of what Japanese couples’ believe about women’s fertility patterns could lead these couples to have their children before the woman turns 40.
