BACKGROUND: Mental health conditions are common and can have significant effects during the perinatal period. Our objective was to determine the incidences and predictors of psychiatric conditions during pregnancy and postpartum among universally insured American women. MATERIAL AND METHODS: This was an Institutional Review Board (IRB)-approved protocol using a retrospective cohort of 104,866 deliveries covered by TRICARE from 2005 to 2014. We used TRICARE claims data to identify pregnant women without current psychiatric conditions who developed new psychiatric condition(s) during pregnancy or postpartum compared with those who did not, as identified by International Classification of Diseases (ICD)-9 CM codes. Predictors of psychiatric conditions during pregnancy or postpartum were determined using stepwise logistic regression models. RESULTS: A total of 104,866 women met the inclusion criteria; of these, 35% (n = 36,192) were diagnosed with a new psychiatric condition during pregnancy or within 1 year of delivery, 15% (n = 15,636) with a psychiatric condition during pregnancy, and 20% (n = 20,556) with a psychiatric condition within 1 year of delivery. We demonstrated that the African-American race (odds ratio [OR] 1.16, 95% CI 1.10-1.22), active duty status (OR 1.20, 95% CI 1.14-1.25), and severe maternal morbidity during delivery (OR 1.18, 95% CI 1.02-1.35) were significantly associated with the occurrence of a psychiatric condition within 1 year of delivery. For Asian women, there was a 28% higher odds of developing a psychiatric disorder during pregnancy (adjusted OR 1.28, 95% CI 1.17-1.40) compared with White women. Active duty women were twice as likely to be diagnosed with post-traumatic stress disorder (adjusted OR 2.31, 95% CI 1.83-2.90). CONCLUSION: In a universally insured population, the incidences of psychiatric conditions in pregnancy and within a year of delivery were similar to the American population. Additionally, the development of psychiatric conditions in pregnancy and within a year of delivery may be associated with race, active duty status, and complicated births.