Gestational Diabetes mellitus which is carbohydrate intolerance that begins with onset or first recognition during pregnancy. It is classified in to pre- gestational Diabetes which is diagnosed before pregnancy. The diagnostic Categories are GDM A1 and A2. 15% of GDM remain diabetic (Type 2) where as 50-60% of GDM will become diabetic in 5-10 yrs. Type-2 GDM encompasses insulin resistance and relative insulin deficiency. It is Associated with obesity or increased percentage of body fat. Both GDM and Type 2 are heterogeneous disorders and their pathophysiology is characterized by peripheral insulin resistance, decreased insulin production and impaired regulation of hepatic glucose production.
Physiology in Gestational Diabetes mellitus are Gestational hormones induce insulin resistance and inadequate insulin reserve and hyperglycemia. The fetal risks are Macrosomia which are shoulder dystocia and related complications, Jaundice, Hypoglycemia and no increase in congenital anomalies. The maternal risks are C-section, pre-eclampsia, recurrence risk of GDM is 30-50%,30-60% lifetime risk in developing IFG, IGT or type 2 diabetes. All women should be screened for GDM between 24-28 weeks and those with multiple risk factors should be screened in the first trimester. The risk factors in first trimester are > 35 yrs, BMI > 30, delivery of a mascrosomic baby, Corticosteroid use.
The Management of Gestational Diabetes is to achieve glycemic targets, receive nutrition counseling from an registered Dietitian, encourage physical activity, avoid ketosis and if blood glucose targets are not reached within 2 weeks then insulin therapy should be started. Nutrition Therapy is the best treatment for GDM to achieve appropriate nutrition, glycemic goals of pregnancy and to normalize fetal growth and birth weight.
Medical nutrition Therapy for GDM is a carbohydrate controlled meal plan with adequate nutrition for appropriate weight gain, normoglycemia, and the absence of ketones. The clinical outcomes is to achieve and maintain normoglycemia, promote adequate calories for weight gain in absence of ketones and to consume food providing adequate nutrients for maternal and fetal health.