Women's emotional and sexual attraction to men across the menstrual cycle

There is ongoing debate about how and why the menstrual cycle affects women’s attraction to men. According to the dual sexuality hypothesis, women form pair-bond relationships with men who provide care but also obtain genetic benefits by biasing mating effort towards men with high-fitness genes during the fertile phase. By contrast, the commitment hypothesis proposes that attachment bonds with primary partners function to strengthen pair-bond relationships by enhancing in-pair attraction at the fertile phase, rather than extra-pair attraction. We tested these hypotheses by measuring women’s daily sexual and emotional attraction towards men over the whole menstrual cycle. We employed (1) a urinary luteinizing hormone test to determine the day of ovulation, (2) a five-part classification of menstrual cycle that identifies a distinct peri-ovulatory phase, and (3) individualized phase identification for each participant. There was a mid-cycle rise in extra-pair sexual desire. Women gav...