Introduction: Gestational diabetes is the most common medical disorder during pregnancy that result in maternal and neonatal complications.this study was to evaluate the BMI demographic variables in pregnant women with gestational diabetes were performed.

Methodology: In this cross-sectional study of 363 pregnant women who had 24 to 28 week of gestation referred to Zabol health centers� And history of diabetes before pregnancy, termination of pregnancy before 24 weeks administration of drugs effecting glucose metabolism such as steroids and patients who have chronic liver disease, glandular and connective tissue disorders were studied. Information on the objectives of the study were collected using a questionnaire.

Results: 17 cases or 4/7 percent� Of all subjects, were diagnosed with gestational diabetes Among the risk factors surveyed� maternal age, body mass index with increased risk of gestational diabetes (p <0/05) . there was no statistically significant relationship Between occupation, education level with gestational diabetes.

Conclusion: High and low maternal age and BMI can contribute to complications of pregnancy, Thus pregnancy in women with older age and abnormal weight should be considered as a high-risk pregnancy Special care in order to prevent the occurrence of this complication.