The Effect of Nutrition Education on Gestational Weight Gain based on the Pender's Health Promotion Model: A Randomized Clinical Trial Study

Weight gain more than the recommended range by the Institute of Medicine (IOM) is one of the most common complications of pregnancy, which would be ended to gestational diabetes, preeclampsia, cesarean section, or maternal, and child obesity. Few successful studies in this area include nutrition and physical activity. We examined a simple, practical, and cost-effective solution as nutrition training based on the Pender’s model, because this is one of the most effective patterns for nutritional behavior.

This single-blind randomized controlled clinical trial study was performed on 192 nulliparous pregnant women. During training sessions, mothers of intervention group learned how to prevent excessive weight gain over healthy eating habits. Mothers’ weight, nutrients intake, and physical activity levels were estimated before, during, and after intervention.

The constructs of perceived benefits, perceived self-efficacy, behavior-related feelings, interpersonal influences, competing demands and preferences, and commitment to action increased significantly. In the intervention group, 58.6% gained weight within the recommended range compared to 50.0% in control group. Moreover, 28.7% in the intervention group versus 45.6% in the control gained weight more than the IOM limits while 12.6% in the intervention group and 4.4% in the control gained weight less (P = 0.020). The perceived self-efficacy and commitment to the plan constructs were associated with normal weight gaining.

Pender model-based nutrition education considering the national guideline prevented excessive gestational weight gain in pregnant women.