Sample size
We have planned to recruit and then follow up a minimum of 268 pregnant mothers in the intervention areas and 268 pregnant mothers in the control areas. According to a study conducted in Ethiopia, the implementation of mHealth services using both voice calls and text messages increased facility delivery by 14.7% in the intervention group compared to the control group (43.1% compared to 28.4%; AOR: 1.98 (95%CI: 1.53, 2.55)) [-----------------------------------------Here,ppzzg = 1.50 (design effect)non-response rate = 5%-----------------------------------------      Based on the logic, we anticipate that the sample size will have enough statistical power to meet the primary objective of our study.