Perinatal mental health disorders affect more than one in five people and obstetrician/gynecologists (Ob/Gyns) are the primary providers for women during the reproductive years when there is increased risk of psychiatric morbidity. Therefore, Ob/Gyns are charged with screening and treating these disorders. Despite the availability of effective strategies for detection and treatment, perinatal mental health disorders are underrecognized and undertreated, and have significant detrimental maternal and infant consequences. Obstetrician/gynecologists should be prepared to counsel patients on the benefits and risks of psycho-pharmacotherapy, initiate psycho-pharmacotherapy, and refer patients to appropriate resources when indicated. A validated screening tool should then be used to monitor for response to treatment or remission of symptoms. Psychotherapy should be considered a first-line treatment for mild-to-moderate perinatal depression and selective serotonin reuptake inhibitors be used as first-line pharmacotherapy for perinatal depression and anxiety. Pharmacotherapy should be individualized based on prior response to therapy and optimal dosing established to avoid undertreatment. The risks associated with inadequately treated mental health conditions as well as the perinatal risks associated with psychopharmacologic agents must be addressed. Furthermore, a discussion about duration of treatment, need for long term follow-up, and considerations for future pregnancy is needed.