Can Men Detect Ovulation?

In contrast to our closest cousin, the chimpanzee, humans appear at first to lack cues of impending ovulation that would mark the fertile period in which a female can become pregnant. Consequently, that ovulation is ‘‘concealed’’ in women has long been the consensus among scientists studying human mating. A recent series of studies shows, however, that there are discernible cues of fertility in women’s social behaviors, body scents, voices, and, possibly, aspects of physical beauty. Some of these changes are subtle, but others are strikingly large (we report effect sizes ranging from small, d 1⁄4 0.12 to large, d 1⁄4 1.20). Moreover, emerging evidence suggests that women’s male partners may adaptively shift their behavior in response to cues of approaching ovulation. These results have far-reaching implications for understanding fluctuations in attraction, conflict, and relationship dynamics.