Many perinatal people experienced pandemic-related distress and changes in health behaviors at the onset of the COVID-19 pandemic, but less is known about how the pandemic continued to impact their health. The authors of this study examined the influence of pandemic-related distress and maternal mental health on postpartum lifestyle behaviors of mothers with a previous hypertensive disorder of pregnancy. Between September 2021 and March 2022, 82 postpartum (19.2 ± 5.5 months) mothers with a hypertensive disorder of pregnancy completed measures of pandemic-related distress and pandemic-related disruption in lifestyle behaviors from the Coronavirus Perinatal Experiences Impact Survey. A Patient Health Questionnaire-9 score ≥ 10 and a score ≥ 3 on the Breslau scale indicated significant depressive and posttraumatic stress disorder (PTSD) symptoms, respectively. Twenty-two (27.2%) and 30 (36.6%) participants had significant depressive or PTSD symptoms, respectively. In models adjusted for education, income, parity, delivery prepandemic or peripandemic, intervention group, and prepregnancy mental health history, both PTSD symptoms (B = 0.229, P = .029) and pandemic-related distress (B = 0.492, P < .001) associated with greater disruption in health behaviors. Depressive symptoms did not associate with greater disruption in health behaviors (B = 0.169, P = .135). Monitoring PTSD symptoms may be vital in supporting mothers with hypertensive disorders of pregnancy in making lifestyle changes to prevent cardiovascular disease.