PURPOSE: Although many women experience obsessive-compulsive symptoms during the perinatal period, the Yale-Brown Obsessive Compulsive Scale (YBOCS) has not yet been psychometrically evaluated in this population. This study examined the internal consistency, convergent and divergent validity, and factor structure of the YBOCS among pregnant women.

METHODS: 256 Women who were 20 to 24 weeks pregnant completed the clinician-administered YBOCS and Mini International Neuropsychiatric Interview (MINI) along with a series of self-report questionnaires including the Edinburgh Postnatal Depression Scale (EPDS), Perinatal Anxiety Screening Scale (PASS) and Obsessive-Compulsive Inventory-Revised (OCI-R).

RESULTS: Internal consistency of the YBOCS was excellent, and there were strong inter-scale correlations between the YBOCS Total Score, YBOCS Obsessions and Compulsions Severity Scales. The YBOCS demonstrated good known-groups validity differentiating women with and without OCD. Convergent validity with the OCI-R was demonstrated while relations with divergent validity were more mixed.

CONCLUSION: The YBOCS possesses strong psychometric properties in pregnant women.