Effects of Hormonal Contraceptives on Estrogen and Progesterone

In “The Cutest Little Baby Face: A Hormonal Link to Sensitivity to Cuteness in Infant Faces,” Sprengelmeyer et al. (2009) reported results from three fascinating studies designed to test humans’ ability to discriminate among infants on the basis of cuteness. The first study indicated that women of reproductive age are superior to men and older women in this regard, and the second study revealed that premenopausal women perform better than age-matched postmenopausal women. Sprengelmeyer et al. compellingly argued that these findings, taken together, strongly indicate that female reproductive hormones (specifically, the two principal hormones, estrogen and progesterone) play a role in sensitivity to cuteness. The authors sought to explore this possibility in a third study, in which they tested women who were taking exogenous hormones for contraception. They found that such women differentiate cuteness in infant faces better than naturally cycling women do. The authors interpreted this result as consonant with their hypothesis about the contribution of estrogen and progesterone to cuteness detection—that oral contraceptives “raise hormone levels artificially” (p. 149). Although hormonal differences between the two groups may have been responsible for this difference, it is unlikely that the effect was due to elevated levels of estrogen and progesterone in the women using oral contraceptives. Contrary to many researchers’ beliefs, oral hormonal contraceptives actually suppress ovarian production of these hormones.