question: OBJECTIVE: To assess the effect of a consumer-based mobile meditation application (app) on wellness in outpatient obstetric and gynecology patients during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: We conducted a randomized controlled trial at a university outpatient clinic of obstetric and gynecology patients during the COVID-19 pandemic. Women were randomly assigned to the intervention group, who was prescribed a mobile meditation app for 30 days, or the control group, which received standard care. The primary outcome was self-reported perceived stress. Secondary outcomes included self-reported depression, anxiety, sleep disturbance, and satisfaction with the meditation app. A sample size of 80 participants (40 per group) was calculated to achieve 84% power to detect a 3-point difference in the primary outcome. RESULTS: From April to May 2020, 101 women were randomized in the study—50 in the meditation app group and 51 in the control group. Analysis was by intention-to-treat. Most characteristics were similar between groups. Perceived stress was significantly less in the intervention group at days 14 and 30 (mean difference 4.27, 95% CI 1.30–7.24, P=.005, d=0.69 and mean difference 4.28, 95% CI 1.68–6.88, P=.002, d=0.69, respectively). Self-reported depression and anxiety were significantly less in the intervention group at days 14 and 30 (depression: P=.002 and P=.04; anxiety: P=.01, and P=.04, respectively). Sleep disturbance was significantly less in the intervention group at days 14 and 30 (P=.001 and P=.02, respectively). More than 80% of those in the intervention group reported high satisfaction with the meditation app, and 93% reported that mindfulness meditation improved their stress. CONCLUSION: Outpatient obstetric and gynecology patients who used the prescribed consumer-based mobile meditation app during the COVID-19 pandemic had significant reductions in perceived stress, depression, anxiety, and sleep disturbance compared with standard care. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT04329533.