Objective: This study examines the association between maternal childhood maltreatment and psychopathology and aggression in intimate relationships during pregnancy and the postpartum period. Method: Forty-four pregnant women who were recruited from an obstetric clinic and local advertising periodical completed questionnaires about childhood maltreatment and psychopathology during their first trimester of pregnancy. Approximately 1 year after the birth of the child, 32 of the original participants completed these same questionnaires. Regression models were used to test the relationship between childhood maltreatment and psychopathology and aggression during pregnancy and 1 year postpartum. Results: Sexual abuse and emotional neglect were related to psychopathology during pregnancy, and emotional neglect and physical abuse and neglect predicted poorer maternal outcomes 1 year postpartum. Contrary to expectations, physical abuse was related to less aggression during pregnancy, and emotional abuse was associated with less pathology postpartum. Conclusions: The results of this study indicate that childhood maltreatment is associated with poorer maternal mental health during pregnancy and 1 year postpartum and points to the need to improve targeting and treatment of psychopathology during this time.