Menken J, Trussell J, Larsen U
Science. 1986 Sep 26;233(4771):1389-94. doi: 10.1126/science.3755843.
Direct evidence on age patterns of infecundity and sterility cannot be obtained from contemporary populations because such large fractions of couples use contraception or have been sterilized. Instead, historical data are exploited to yield upper bounds applicable to contemporary populations on the proportions sterile at each age. Examination of recent changes in sexual behavior that may increase infecundity indicates that sexually transmitted infections, the prime candidate for hypothesized rises in infertility, are unlikely to have added to infecundity to any great extent. These results imply that a woman in a monogamous union faces only moderate increases in the probability of becoming sterile (or infecund) until her late thirties. Nevertheless, it appears that recent changes in reproductive behavior were guaranteed to result in the perception that infecundity is on the rise.
由于很大一部分夫妇使用避孕措施或已绝育，所以无法从当代人口中获得关于生育力低下和不育症年龄模式的直接证据。相反，利用历史数据得出适用于当代人口的各年龄不育比例上限。对近期可能增加生育力低下的性行为变化进行的研究表明，性传播感染作为不育症假设性上升的主要候选因素，不太可能在很大程度上增加生育力低下的情况。这些结果表明，处于一夫一妻制关系中的女性在接近四十岁之前，不育（或生育力低下）的概率只会适度增加。然而，近期生殖行为的变化似乎必然导致人们认为生育力低下情况正在上升。
