Principal Findings
To the best of our knowledge, this is the first trial that combines mHealth and PFMT to prevent and treat UI symptoms in Chinese pregnant women. The results of this study support the effectiveness of UIW app–based interventions in reducing UI symptom severity, UI impact on life, and enhancement of PFMT self-efficacy and UI-related knowledge among pregnant women. This could help to update the Cochrane review to determine the effect of antenatal PFMT as a mixed preventive and therapeutic strategy for UI.Greater improvements in the severity of UI symptoms were observed at 2 months after randomization in the experimental group than in the control group, and the improvement was sustained at 6 weeks post partum. These findings were in line with those of previous studies conducted on community-dwelling women with SUI using app-based treatment programs compared with no treatment [The mean between-group differences in symptom severity score reduction (2.86 at 2 months after randomization; 2.68 at 6 weeks post partum) were slightly smaller than those achieved in similar studies using a mobile app for self-management of UI [The sustained improvement in quality during daily life and self-efficacy with PFMT and UI-related knowledge in the experimental group also showed encouraging results. The beneficial effects may be because the UIW app is an evidence-based and multifunctional tool based on behavior change techniques [Previous qualitative interviews also showed that the app could help increase individuals’ confidence in performing PFMT independently and their awareness of UI symptoms [