PLAN: Women who present for prenatal care are routinely screened for gestational diabetes (GDM) with a one-hour 50gm oral glucose challenge test (GCT). This screening occurs at the first prenatal visit if risk factors (marked obesity, prior pregnancy affected by GDM, prior macrosomic infant, glycosuria, strong family history of diabetes) for GDM are identified on intake history. If no risk factors for GDM are identified or if initial screening is negative, the GCT is administered between 24-28 weeks gestation. At our institution, the GCT is considered positive if, one hour after ingestion of a 50gm oral glucose solution, the serum glucose is greater than or equal to 135mg/dl. This screening cutoff varies among medical treatment facilities. Positive screening tests are followed by a diagnostic oral glucose tolerance test (GTT). A positive diagnosis requires that two or more thresholds be met or exceeded. Women with the diagnosis of gestational diabetes will receive dietary counseling and instruction on the performing capillary glucose from a by a nurse educator. If > 20% of recorded home glucose values are in excess of target range following initiation of appropriate diet, women will be offered enrollment into the study.