High estradiol and low progesterone are associated with high assertiveness in women

• Published in: Psychoneuroendocrinology Vol. 75; pp. 91 - 99
• Main Authors: Blake, Khandis R., Bastian, Brock, O’Dean, Siobhan M., Denson, Thomas F.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2017
• Subjects: Adult; Assertiveness; Endocrinology & Metabolism; Estradiol; Estradiol - metabolism; Female; Fertility; Humans; Mate selection; Progesterone; Progesterone - metabolism; Psychiatry; Sexual Behavior - physiology; Sexual motivation; Young Adult; Sexual motivation; Mate selection; Progesterone; Fertility; Estradiol; Assertiveness
• ISSN: 0306-4530; 1873-3360; 1873-3360
• DOI: 10.1016/j.psyneuen.2016.10.008

•We investigated whether fertility and hormones influenced assertiveness in women.•High estradiol and low progesterone were positively associated with high assertiveness.•High assertiveness was positively associated with high sexual motivation.•We propose that high assertiveness when fertile may promote mate selectivity.•High assertiveness when fertile may safeguard against indiscriminate mate choice. Sexual selection theory posits that women are more selective than men are when choosing a mate. This evolutionary theory suggests that “choosiness” increases during the fertile window because the costs and benefits of mate selection are highest when women are likely to conceive. Little research has directly investigated reproductive correlates of choice assertion. To address this gap, in the present research we investigated whether fertility, estradiol, and progesterone influenced general assertiveness in women. We recruited 98 naturally cycling, ethnically diverse women. Using a within-subjects design and ovarian hormone concentrations at fertile and non-fertile menstrual cycle phases, we measured implicit assertiveness and self-reported assertive behavior. To see if fertility-induced high assertiveness was related to increased sexual motivation, we also measured women’s implicit sexual availability and interest in buying sexy clothes. Results showed that high estradiol and low progesterone predicted higher assertiveness. Sexual availability increased during periods of high fertility. Low progesterone combined with high estradiol predicted greater interest in buying sexy clothes. Results held when controlling for individual differences in mate value and sociosexual orientation. Our findings support the role of fluctuating ovarian hormones in the expression and magnitude of women’s assertiveness. High assertiveness during the fertile window may be a psychological adaptation that promotes mate selectivity and safeguards against indiscriminate mate choice when conception risk is highest.