Can women’s hormonal cycle influence their voting preferences? A recent study aimed to replicate and expand upon earlier research, which had suggested that women’s fertility could sway their support for political candidates. The findings, published Psychological Reports, failed to find much evidence for a connection between fertility and political preferences. However, the research did uncover a weak relationship between psychopathic personality traits and support for Donald Trump.
The original study, published in 2010, was grounded in the broader ovulatory shift hypothesis, which posits that hormonal changes across a woman’s menstrual cycle can influence various preferences and behaviors, including mate selection. The research provided initial evidence that during fertile periods, women might favor Barack Obama over John McCain in the 2008 U.S. presidential election due to perceived cues of genetic fitness.
But why revisit this research? Jessica L. Engelbrecht of the New School for Social Research noted that the initial study, though innovative, had important methodological limitations, including a small sample size and a homogenous participant group of young, white women. Moreover, subsequent research has provided mixed evidence regarding the ovulatory shift hypothesis, with some studies finding no significant effect of fertility on women’s mate preferences or sexual desires.
This context set the stage for a rigorous replication attempt under the Systematizing Confidence in Open Research and Evidence (SCORE) program, aiming to clarify these contentious findings within the field of evolutionary psychology.
Conducted between July and August 2020, Engelbrecht and her colleagues recruited a sample of 549 female participants from the United States, who were carefully selected to ensure a representative sample in terms of age, ethnicity, and other demographic factors. These participants were chosen based on their menstrual cycle regularity, absence of pregnancy, non-use of hormonal birth control, and lack of chronic health issues affecting fertility, aiming to isolate the impact of natural hormonal fluctuations on political preferences.
Participants provided detailed information about their menstrual cycles, including the average length and the start date of their last period. This information was crucial for calculating each participant’s conception risk at the time of the survey.
The survey then presented participants with a series of hypothetical electoral matchups featuring a mix of Democratic and Republican candidates, including Donald Trump, Barack Obama, Joe Biden, and others. These matchups were designed to replicate the conditions of the original study, while also reflecting the contemporary political landscape and testing the hypothesis in a new context. Participants indicated their preferred candidate in each matchup and rated each candidate on attributes such as physical attractiveness, perceived intelligence, and potential for sexual coercion.
In addition to political preferences, the survey collected data regarding political orientation, self-assessed mate value, and the Dark Triad personality traits — Machiavellianism, narcissism, and psychopathy. These measures aimed to explore how individual personality characteristics and self-perception might influence political preferences, providing a comprehensive view of the factors at play.
The researchers discovered that the conception risk, calculated based on participants’ menstrual cycle information, had a minimal impact on voting preferences in the majority of the electoral matchups tested. Notably, the only significant relationship between conception risk and voting preference emerged in the matchup between Trump and Obama.
In this case, a weak but statistically significant correlation indicated that higher conception risk was associated with a slightly increased likelihood of preferring Donald Trump over Barack Obama. However, this effect was small, suggesting that factors beyond fertility might play a more crucial role in shaping political preferences.
When examining the influence of candidates’ perceived intelligence, attractiveness, and potential for sexual coercion, the researchers found that perceptions of intelligence were more predictive of voting preference than attractiveness. This challenges the hypothesis that visual cues of genetic fitness significantly influence voter preferences, suggesting instead that intellectual competence may be a more critical factor for voters.
When examining Dark Triad personality traits, Engelbrecht and her colleagues found that psychopathy showed a significant, albeit weak, relationship with a preference for Trump in the matchups where he was featured. This finding suggests that women with higher levels of subclinical psychopathy, characterized by impulsivity and remorselessness, were slightly more inclined to support Trump, irrespective of the specific electoral matchup.
“Overall, the current manuscript offers no substantive support to the first study of Navarrete et al. (2010). We were unable to replicate their key finding… Rather, our results suggest that women’s perception of the candidates’ intelligence, and their own personalities, have some relationship to their stated voting preferences,” the researchers concluded. “Although the comparability of our findings must be considered in light of the impossibility of a direct replication of the original, we contend that hormonal changes across the menstrual cycle are unlikely to tip the scale for female voters.”
The study, “Fertility Fails to Predict Voter Preference for the 2020 Election: A Pre-Registered Replication of Navarrete et al. (2010),” was authored by Jessica L. Engelbrecht, Matthew Duell, and John E. Edlund.
