WOMEN with high levels of a key sex hormone are judged more attractive by themselves and others, and may be more inclined to cheat on their partners, according to a study published early this month.
University of Texas psychologists Kristina Durante and Norman Li found that women with high concentrations of the hormone oestradiol were likelier to flirt, kiss and have a serious affair outside an established relationship.
In a study published in the British journal Biology Letters, the duo described the behaviour as â€œopportunistic serial monogamyâ€ and not related to one-night stands. Instead, they suggested, such women were more probably being prompted to trade up in their relationships â€” to find a better partner.
Other studies of oestradiol have shown that higher levels of the hormone are closely linked to enhanced fertility among women.
As a result, men have an evolved response that prompts them to pick up on telltale signs of the hormone's presence.
High concentrations of oestradiol are associated with big breasts, facial attractiveness and low waist-to-hip ratio.
Durante and Li measured hormone levels at two different stages of the menstrual cycle among 52 women aged 17 to 30, who were not taking the pill.
The women were asked to rate their own attractiveness and sexiness â€œcompared to other women,â€ their satisfaction with current partners, their willingness to engage in uncommitted sex and about their past relationships.
Separately, a panel of men and women unaware of the experiments evaluated photos of the women, rating them for attractiveness.
The women with the highest levels of oestradiol reported a greater likelihood of having a serious affair. They also reported a greater number of long-term relationships in the past.
Sex hormone makes women cheat