Menstrual cycle and hormonal contraception effects on self-efficacy, assertiveness, regulatory focus, optimism, impulsiveness, and risk-taking

Abstract

The Fertility-Assertiveness Hypothesis posits that women affect their environment and assert their desires more so during the fertile compared to non-fertile phase of their menstrual cycle. No research to date has examined whether this increase is evident in other psychological outcomes loosely related to assertiveness or whether it is attenuated by hormonal contraception. To address these gaps we implemented The Daily Cycle Diary, a worldwide daily diary study examining menstrual cycle and hormonal contraception induced shifts in assertiveness, self-efficacy, optimism, regulatory focus, impulsivity and risk-taking. In a fully pre-registered, quasi-experimental within-subject investigation, participants from 23 countries (939 menstrual cycles) provided daily data on their menstrual cycle characteristics and answered self-report questions on each day of their menstrual cycle. Self-efficacy robustly increased alongside fertility probability for naturally cycling women but not hormonal contraceptive users. Prevention-focus (a regulatory strategy that avoids negative outcomes) also increased with fertility probability but the effect was not robust. Menstruation was associated with lowered assertiveness as well as changes in three facets of impulsivity for all women, irrespective of contraceptive use. Exploratory plots showed that contraceptive users and naturally cycling women exhibit a variety of menstrual cycle induced psychological differences unrelated to cycling fertility. Given the prevalence of hormonal contraception use worldwide, future investigation of the menstrual cycle and hormonal contraceptive use on female psychology is of utmost importance.