Effectiveness of a Reminder System in Increasing Antenatal Care Utilisation Among High-Risk Pregnant Women in Indonesia: A Quasi-Experimental Study

Background: Antenatal care is crucial for high-risk pregnancies, but utilisation remains suboptimal in Indonesia due to barriers like limited access and low awareness. Digital interventions can improve healthcare adherence globally. Objective: To evaluate the effectiveness of a mobile-based reminder system in increasing Antenatal Care (ANC) utilisation among high-risk pregnant women in Indonesia. Methods: A quasi-experimental pretest-posttest control group design was carried out in Bekasi, Indonesia, from May to August 2024. The trial included 150 high-risk pregnant women who were randomly assigned to one of two groups: intervention (75) or control (75). The intervention group received personalised reminders via SMS and mobile app notifications, whereas the control group received conventional ANC services. ANC usage was evaluated using the World Health Organization's (WHO) ANC Quality Assessment Tool. The data was analysed using paired t-tests and ANCOVA to assess within-group changes and between-group differences. Results: The intervention group improved ANC utilisation significantly in all domains, including facility support (mean difference = 1.3, p < 0.001), routine care (mean difference = 1.5, p < 0.001), and complication management (mean difference = 1.4, p < 0.001). In contrast, no significant differences were seen in the control group. ANCOVA showed that the intervention group had significantly higher post-test scores than the control group (p < 0.001). Conclusion: The reminder system significantly improved ANC utilisation among high-risk pregnant women in Indonesia. Future research should explore long-term impacts and scalability of such interventions.