The evidence for good genes ovulatory shifts in Arslan et al. (2018) is mixed and uncertain

Ovulatory cycle shifts in human motivational prioritisation of sex and food

Previous research on the endogenous effects of ovarian hormones on motivational states in women has focused on sexual motivation. The Motivational Priority Shifts Hypothesis has a broader scope. It predicts a shift from somatic to reproductive motivation when fertile. In a highly powered preregistered online diary study across 40 days, we tested whether 390 women report such an ovulatory shift in sexual and eating motivation and behaviour. We compared 209 naturally cycling women to 181 women taking hormonal contraceptives (HC) to rule out non-ovulatory changes across the cycle as confounders. We found robust ovulatory decreases in food intake and increases in general sexual desire, in-pair sexual desire and initiation of dyadic sexual behaviour. Extra-pair sexual desire increased mid-cycle, but the effect did not differ significantly in HC women, questioning an ovulatory effect. Descriptively, solitary sexual desire and behaviour, dyadic sexual behaviour, appetite, and satiety showed expected mid-cycle changes that were diminished in HC women, but these failed to reach our strict preregistered significance level. Our results provide insight into current theoretical debates about ovulatory cycle shifts while calling for future research to determine motivational mechanisms behind ovulatory changes in food intake and considering romantic partners' motivational states to explain the occurrence of dyadic sexual behaviour.

Women's Estrus and Extended Sexuality: Reflections on Empirical Patterns and Fundamental Theoretical Issues

How do women's sexual interests change across their ovulatory cycles? This question is one of the most enduring within the human evolutionary behavioral sciences. Yet definitive, agreed-upon answers remain elusive. One empirical pattern appears to be robust: Women experience greater levels of sexual desire and interest when conceptive during their cycles. But this pattern is not straightforward or self-explanatory. We lay out multiple possible, broad explanations for it. Based on selectionist reasoning, we argue that the conditions that give rise to sexual interests during conceptive and non-conceptive phases are likely to differ. Because conceptive and non-conceptive sex have distinct functions, the sexual interests during conceptive and non-conceptive phases are likely to have different strategic ends. We discuss provisional evidence consistent with this perspective. But the exact nature of women's dual sexuality, if it exists, remains unclear. Additional empirical research is needed. But perhaps more crucially, this topic demands additional theory that fruitfully guides and interprets future empirical research.