Body odor disgust sensitivity during pregnancy and the postpartum period: a longitudinal study

Olfactory perception is a key component in the elicitation of disgust. General disgust sensitivity fluctuates during pregnancy as part of the behavioral immune system's protective mechanisms, but it is currently unknown whether a similar pattern applies also specifically to odor-elicited disgust. This longitudinal study examined changes in body odor disgust sensitivity during pregnancy and the postpartum period among 276 women, recruited in health centers. Participants completed questionnaires focused on body odor disgust, general pathogen disgust, anxiety, and nausea and vomiting in pregnancy at multiple points from early pregnancy until six months postpartum. The results revealed that body odor disgust sensitivity peaked in the first trimester, declined through the later trimesters, and reached its lowest point in the early postpartum period before increasing again at six months postpartum. This trajectory was found for body odor disgust directed at both own and other person's bodies. Importantly, body odor disgust sensitivity could not be explained solely by general pathogen disgust sensitivity, which suggests a distinct role for olfactory disgust in pregnancy. Our findings support the Compensatory Prophylaxis Hypothesis, which highlights the adaptive increase in disgust sensitivity during the especially vulnerable period of early pregnancy. The postpartum decline in body odor disgust may reflect either desensitization to infant odors or reduced social exposure. Future research could further explore the physiological and psychological factors which contribute to these changes.