Ovulating women exhibit a preference for more masculine male features, are particularly attracted to men showing dominance and male-male competitiveness and prefer partners that are genetically dissimilar to themselves. This is significant because there is evidence suggesting that genetic similarity between couples might be linked with infertility. Further, some studies have suggested that men detect women's fertility status, preferring ovulating women in situations where they can compare the attractiveness of different women.
The oral contraceptive pill alters the hormonal fluctuations associated with the menstrual cycle and essentially mimics the more steady hormonal conditions associated with pregnancy ... The authors also speculate that the use of oral contraceptives may influence a woman's ability to attract a mate by reducing attractiveness to men, thereby disrupting her ability to compete with normally cycling women for access to mate.
Of particular interest is the fact that women taking the pill do not exhibit the ovulation-specific attraction to genetically dissimilar partners. ...Implications are that a woman on the pill is more likely to end up with a wimp for a husband and inbred children. A woman who prepares herself for getting a macho man may end up pregnant instead.