butkaf t1_ive6k5r wrote on November 7, 2022 at 8:50 AM

Women can smell when men have a certain gene (major histocompatibility complex) that differs from theirs. The greater the difference, the greater the variability of resistance to certain microorganisms. This has an impact on mate selection and women prefer the scents of men who have differing MHC genes to men who have more similar MHC genes

therealdilbert t1_ivfoeew wrote on November 7, 2022 at 5:07 PM

and afaiu there is some indication that birth-control pills can mess with that mechanism, so a man a women finds attractive while on the pill might be the total opposite when she gets off the pill to have kids with that man ...