High estradiol and low progesterone are associated with high assertiveness in women.
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.
School of Psychology, Mathews Building, The University of New South Wales, UNSW Sydney NSW 2052, Australia. Electronic address: k.blake@unsw.edu.au.
Khandis R
KR
Blake
School of Psychological Sciences, Redmond Barry Building, The University of Melbourne, Parkville VIC 3010, Australia.
Brock
B
Bastian
School of Psychology, Mathews Building, The University of New South Wales, UNSW Sydney NSW 2052, Australia.
Siobhan M
SM
O'Dean
School of Psychology, Mathews Building, The University of New South Wales, UNSW Sydney NSW 2052, Australia.
Thomas F
TF
Denson
D000328:Adult; D001242:Assertiveness; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D006801:Humans; D011374:Progesterone / Q000378:metabolism*; D012725:Sexual Behavior / Q000502:physiology*; D055815:Young Adult
D011374:Progesterone; D004958:Estradiol
Assertiveness; Estradiol; Fertility; Mate selection; Progesterone; Sexual motivation