Infidelity Across the Ovulatory Cycle

Abstract

The circumstances under which infidelity occurs are numerous and several characteristics predict prior and future infidelity (e.g., religiosity, number of lifetime sexual partners, sociosexuality). Evolutionary perspectives inform why steroid hormones that vary across the ovulatory cycle have been associated with both women’s interest in extrapair partners and shifting expressions of men’s anti-infidelity behavior across their partner’s ovulatory cycle. This chapter provides an overview of the ovulatory cycle to establish the physiological basis of the hormonal changes that occur across it. It then provides requisite background on evolutionary theories of human mating, which provide a framework to predict when women should express the most interest in extrapair partnerships, how current partner qualities are associated with desire for extrapair mating opportunities, and the types of qualities women may be seeking in extrapair partners. Evidence that supports and contradicts these accounts of ovulatory phase-dependent changes in extrapair partnerships, as well as research on male anti-infidelity strategies, is then considered. Finally, the chapter reviews evidence that hormonal contraceptives may alter partner preference patterns established in naturally cycling women and their opposite-sex partners. It concludes by identifying current gaps in hormone-linked shifts in women’s infidelity desires and behavior, and makes recommendations for future research.