To investigate obstetric care provider attitudes toward perinatal depression screening and factors associated with variable screening rates. Provider attitudes about depression screening were investigated via structured interviews (open-ended and rating scale questions) and analyzed using qualitative content analysis. Most providers (86%) found screening effective at identifying women at risk for perinatal depression (average rating of 8.7 on 10-point analog scale). However, 95% overestimated their own screening rates and 67% inaccurately thought they achieved universal screening. Providers not directly involved in their office-based screening process demonstrated lower average screening rates (37%) than those who maintained active involvement (59%; p = 0.07). Obstetric care providers support perinatal depression screening in the context of a program that assumes responsibility for processing screens, conducts assessments of at-risk women and provides referrals to mental health professionals. Provider participation in screening and tying screening to routine obstetric outpatient activities such as glucose tolerance testing are associated with higher screening rates.