Prevalence studies show that 1 in 5 women experience an episode of major depressive disorder during their lifetime. The peripartum period is a prime time for symptom exacerbation and relapse of depressive episodes. Health care providers, specifically those in obstetric care, should be aware of: (1) the frequency of depression in pregnant and postpartum women; (2) signs, symptoms, and appropriate screening methods; and (3) the health risks for the mother and growing fetus if depression is undetected or untreated. Because management of depressed peripartum women also includes care of a growing fetus or breastfeeding infant, treatment may be complex and requires input from a multidisciplinary team, including an obstetrician, psychiatrist, and pediatrician, to provide optimal care.