Is pathogen disgust increased on days of the menstrual cycle when progesterone is high? Evidence from a between-subjects study using estimated progesterone levels

The Compensatory Prophylaxis Hypothesis proposes that women will show increased pathogen disgust at points in the menstrual cycle when progesterone is high, compensating for the immunosuppressive effects of progesterone. However, evidence for the Compensatory Prophylaxis Hypothesis from studies that used longitudinal designs to investigate whether pathogen disgust tracks changes in progesterone is mixed. It was recently proposed that longitudinal designs may be poorly suited to testing the Compensatory Prophylaxis Hypothesis because carry- over effects when women are tested repeatedly in within-subject designs might obscure the effects of progesterone and pathogen disgust. Consequently, we used a between-subjects design to test for a positive relationship between scores on the pathogen disgust subscale of the Three Domain Disgust Scale and progesterone levels imputed from menstrual cycle data using actuarial tables. Analyses showed no evidence for a positive effect of progesterone on pathogen disgust, suggesting that null results for the hypothesised relationship between progesterone and pathogen disgust are not limited to studies using designs that may be subject to carry-over effects caused by repeated testing. Thus, our results add to a growing body of research that does not support the Compensatory Prophylaxis Hypothesis.