# Telephone-based lifestyle education to prevent gestational diabetes in high-risk Iranian women: a randomized trial

## TL;DR

A study found that phone-based lifestyle education helped prevent gestational diabetes in high-risk Iranian women and improved their self-care behaviors.

## Contribution

This study demonstrates the effectiveness of telephone-based lifestyle education in preventing gestational diabetes in high-risk populations.

## Key findings

- GDM incidence was significantly lower in the intervention group (10%) compared to the control group (24.4%).
- The intervention group showed better adherence to healthy diet, physical activity, and blood glucose monitoring.
- BMI increase was significantly lower in the intervention group compared to the control group.

## Abstract

Gestational diabetes mellitus (GDM) is a common metabolic disorder during pregnancy, associated with increased maternal and neonatal complications. This study aimed to evaluate the effectiveness of telephone-based lifestyle education in preventing GDM among high-risk Iranian women.

A parallel randomized clinical trial was conducted from October 2024 to June 2025 at primary healthcare centers. Among 1,000 pregnant women assessed for eligibility, 180 high-risk participants with normal baseline blood glucose were selected. Of these, 170 participants were randomly assigned to the intervention (n = 85) and control (n = 85) groups. Five participants from the intervention group and seven from the control group were lost to follow-up, leaving 80 participants in the intervention group and 78 in the control group who completed the study. The intervention group received structured telephone counseling on healthy nutrition, physical activity, weight management, and blood glucose monitoring, while the control group received routine prenatal care. This intervention was delivered via telephone and consisted of seven structured counseling sessions. Data were collected using a checklist of structured questions designed to assess adherence to self-care behaviors, including healthy diet, physical activity, and blood glucose monitoring. The checklist also included questions on demographic information and adherence to the interventions. The primary outcome was GDM incidence at 28 weeks of gestation. Secondary outcomes included changes in BMI and adherence to self-care behaviors. Statistical analysis was performed using IBM SPSS Statistics version 21.

Data were analyzed using chi-square tests for categorical variables and independent t-tests for continuous variables. Multivariable logistic regression was used for the primary outcome. A p-value < 0.05 was considered statistically significant.

At 28 weeks, GDM occurred in 10% of the intervention group compared to 24.4% of controls (p = 0.018). After adjusting for confounders, telephone education was associated with a significant reduction in GDM risk (adjusted OR = 0.37; 95% CI: 0.15–0.88; p = 0.025). BMI increase was lower in the intervention group (0.6 ± 1.1 vs. 1.3 ± 1.4, p = 0.012). Adherence to a healthy diet, regular physical activity, and blood glucose monitoring in the intervention group was 75%, 68%, and 62%, respectively, significantly higher than the control group.

Telephone-based lifestyle education is an effective, accessible, and cost-efficient strategy to prevent GDM in high-risk women and can improve self-care behaviors and weight management during pregnancy.

IRCT registration number: IRCT2017052115995N2 Registration date: 2017-09-22.

The online version contains supplementary material available at 10.1186/s12884-026-08830-x.