In this particular claim (females have a biological motivation to conserve sex), you should research findings regarding female bonobos. EG, from [1]: "bonobo females mate throughout their ovulatory cycles with most or all group males." In other words, females may actually be incentivized towards promiscuity because it confuses paternity, bonding the offspring with multiple group males, increasing its chances for survival.
[1] https://books.google.com/books?id=_scD6LxIuMUC&pg=PA1938&lpg...