Time to Move in Pregnancy Hyperglycemia

Eligibility Criteria * Singleton, viable pregnancy with low suspicion for clinically significant abnormality or aneuploidy * Age 18-40 years (at recruitment) * Comfortable communicating with study staff in English and completing study surveys in English (i.e., no translator needed) * Identified as Gestational Glucose Intolerance (GGI) and a 3-hr 100g OGTT for Gestational Diabetes Mellitus (GDM) performed ≥ 24 weeks (i.e., GGI or GDM), or GDM by the one step procedure or a 1-hr 50-g glucose challenge test (GCT) ≥ 180 mg/dl performed ≥ 24 weeks Identification of GGI 1-hr 50-g GCT (non-fasting), with plasma glucose at 1-hr ≥ 130 mg/dL Identification of GDM by the two-step procedure Identified as GGI, followed by a 3-hr 100g OGTT at ≥ 24 weeks after an overnight fast, with at least two of four plasma glucose values meeting or exceeding: * Fasting: 95 mg/dL * 1-hr: 180 mg/dL * 2-hr: 155 mg/dL * 3-hr: 140 mg/dl Identification of GDM by the one-step procedure 75-g OGTT at ≥ 24 weeks after an overnight fast, with at least one plasma glucose value meeting or exceeding: * Fasting: 92 mg/dL * 1-hr: 180 mg/dL * 2-hr: 153 mg/dL Identification of GDM by 1-hr 50-g GCT 1-hr 50-g GLT (non-fasting), with plasma glucose at 1-hr ≥ 180 mg/dL at ≥ 24 weeks Exclusion Criteria * Indication that physical activity is or should be limited in the current pregnancy * Previously diagnosed with diabetes (i.e., Type I or Type II diabetes) outside of pregnancy * Current use of daily medications kn…