the present study examined the influence of hormones on obsessive-compulsive disorder (ocd) symptoms and related phenomena across the menstrual cycle. after exclusions, 223 participants (51 free-cycling women, 100 hormonal contraceptive users, and 72 men), completed questionnaires on disgust sensitivity, ocd symptoms, responsibility beliefs, risk-taking, and anxiety two weeks apart using a within-subjects design (follicular and luteal phases for free-cycling women). laboratory participants (n = 178) also completed an emotion discrimination task, had 2d:4d measured, and a subset of women provided saliva samples (n = 56). contrary to the compensatory prophylaxis hypothesis, subclinical ocd contamination symptoms, disgust sensitivity, and related phenomena did not increase with progesterone levels. however, changes in salivary progesterone levels across the cycle were positively correlated with changes in anxiety and negatively correlated with risk-taking. sexual activity and level of contamination fears were significant moderators of behavior change across the cycle. non-sexually active (versus sexually active) women and women with high (versus low) contamination fears showed an increase in ocd symptoms from the follicular to the luteal phases. women with pms (versus those without) showed increased ocd symptoms, disgust-sensitivity and responsibility beliefs at both phases of the menstrual cycle. finally, women were more sensitive to detecting facial expressions of disgust than men. greater disgust sensitivity detection was also associated with higher 2d:4d, and use of oral contraceptives with either high progesterone dosage or low androgenicity. the current findings suggest that perhaps not all women experience an increase in precautionary behaviour across the menstrual cycle, but that there may be subgroups of women who are more susceptible to behavioural changes as a result of fluctuating hormone levels.