Effect of smartphone-based behavioral text messaging interventions on gestational weight gain: a randomized controlled trial

This study examined the effects of smartphone-based behavioral text messaging interventions on appropriate gestational weight gain (GWG) and nutritional and physical activity behaviors in accordance with the Institute of Medicine (IOM) guidelines. This single-blind, parallel, randomized controlled experimental trial used a pretest–posttest design. The study was conducted between June 2021 and February 2022 with 90 pregnant women (intervention = 45, control = 45) with normal, overweight, or obese pre-pregnancy body mass index(BMI). Data were collected using an individual questionnaire and the Healthy Lifestyle Behaviors in Pregnancy Scale (HLBPS). The intervention group received text messages three times a week about GWG, nutrition, and exercise, while the control group received standard antenatal care (ANC) messages once a month. Data were analyzed using the R statistical software with a significance level of p < 0.05. No significant difference was found between the intervention and control groups regarding mean total GWG (13.1 ± 4.3 kg and 14.6 ± 4.2 kg, respectively; p > 0.05). However, the proportion of women who achieved appropriate GWG within the 2009 IOM recommendations was significantly higher in the intervention group (48.9%) than in the control group (22.2%) ( p < 0.05). Intra-group increases in the HLBPS total score, and its nutrition and physical activity subscales were significant in the intervention group ( p < 0.05). In the intervention group, the interaction between pregnant women who achieved appropriate GWG according to the IOM guidelines and those who did not was significant for both the HLBPS total score and the nutrition and physical activity subscale scores, indicating that the intervention was effective ( p < 0.05). Smartphone-based behavioral text messaging interventions increased compliance with IOM-recommended GWG and represent a promising approach for weight management during pregnancy. These mobile health interventions may also help overcome common barriers in antenatal care, including time, transportation, resource and staffing constraints. ClinicalTrials.gov identifier NCT05590832, Date of Registration: 10/17/2022.