effectiveness of nutrition education program based on health belief model compared with traditional training on the recommended weight gain during pregnancy

background: the greatest pressure in the physiological life of women is caused during pregnancy due to the occurrence of most important changes in their biological status. weight gain considered as one of the valid indicators of proper nutrition during pregnancy which is evaluated by body mass index (bmi). the aim of this study was to compare the effect of nutrition education program based on health belief model with classical training on the recommended weight gain during pregnancy in pregnant women in gonabad. methods : in this quasi-experimental controlled study, 110 pregnant women referred to urban health centers in gonabad in 2009 were included in two case (54) and control (56) groups.. pre-test data was collected in two studied groups during their first pregnancy care visit by a self-administrated questionnaire. its validity and reliability had been approved previously. the intervention was two educational sessions in case and control groups based on health belief model and traditional model, respectively. post-test data was collected in the last pregnancy care visit. obtained data analyzed by spss software. findings: there were no significant differences between two studied groups regarding age, the education, parity, abortion and jobs. after intervention the most influencing external cue of action was husband in experimental group (%87.03) and healthcare workers in control group (%51.78). after intervention mean score of knowledge, perceived susceptibility, severity, threat, benefits and barriers and nutritional behavior in the experimental group  and mean score of knowledge  in control group changed significantly (p<0.05). there was significant difference in gaining recommended weight during pregnancy between two studied groups (p<0.05). conclusion: while 77.78% of experimental group members achieved recommend mbi, just 32.29% of control group members gained this criterion. this study proved that hbm application in nutritional education was successfully effective to gain recommended weight in pregnancy, so that increasing suitable weight gain reached maximum and unstandardized weight gain reached minimum in accordance with women’s bmi. key words: bmi, health belief model, traditional education, pregnant women, prenatal nutrition