Effect of the smartphone application on caesarean section in women with overweight and obesity: a randomized controlled trial in China

BACKGROUND: The rate of caesarean section (CS) is increasing worldwide. While a CS can be life-saving when medically indicated, it can cause adverse health effects for both women and children. This trial aims to evaluate the effect of the smartphone application, which aims to control the gestational weight gain, on the rate of CS in overweight and obese women. METHODS: Overweight and obese primiparas (BMI ≥ 24 kg/m(2)) with age between 20 and 40 years old were recruited at Beijing Obstetrics and Gynecology Hospital, and randomly assigned into the intervention group (143 cases) and the control group (138 cases). The intervention group applied the smartphone application (App) to control gestational weight gain in addition to the usual care, and the control group received the usual care. Primary outcome was cesarean section (CS) rate. Secondary outcomes included gestational hypertension, preeclampsia and eclampsia, gestational diabetes mellitus, postpartum hemorrhage, neonatal asphyxia, and macrosomia. RESULTS: There was a significant difference in CS rate, with 53.3% in the intervention group and 65.4% in the control group (P = 0.044). The difference still exists in the overweight subgroup (32.6% vs. 55.6%, P = 0.04), but disappears in the obesity subgroup (63.0% vs. 69.1%, P = 0.381). The median of gestational weight gain (GWG) of the intervention group is 8.5 kg (IQR 5.5, 11.0), which is significantly less than that of the control group (median 10.0 kg, IQR [6.0, 14.0], P = 0.008). The intervention group has significantly lower rate of postpartum hemorrhage (5.19%) than the control group (12%) (P = 0.045). There were no significant differences between the groups in gestational hypertension, gestational diabetes mellitus, neonatal asphyxia, and macrosomia. CONCLUSION: The smartphone assisted weight control may help reduce CS rate. The effects of the smartphone application might be via the management of gestational weight gain. TRAIL REGISTRATION: This trial was registered at Chinese Clinical Trial Registry. Registration number is ChiCTR2300068845 (retrospectively registered, 01/03/2023). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12884-023-06004-7.