- Eligible participants will be approached and counseled about the nature of the study. If they are willing to participate, informed consent would be obtained from them and a questionnaire to obtain vital clinical information would be administered. Thereafter, they would be instructed to go to the laboratory to perform 1 hour 50 g glucose challenge test (GCT) with HbA1C (study group) or HbA1C only (control group). The 1-hour GCT involves administration of 50g of glucose solution by mouth. Participants do not need to be fasting. After 1 hour, venous blood will be drawn along with other prenatal labs, and glucose level and HbA1C would be analyzed. The control group will not be given the 1-hour GCT but only perform HbA1C level during their routine prenatal lab tests. Practitioners at UIC routinely request the HbA1C test as standard of care for obese pregnant women at early gestation based on ACOG recommendation.