Glycemic Targets for Pregnant Women With GDM and T2DM

Tight Versus Standard Glycemic Targets for Pregnant Women With Gestational Diabetes and Type 2 Diabetes

The purpose of this randomized clinical trial is to determine whether glycemic targets that are lower than those currently recommended by the American Diabetes Association (ADA) and the American College of Obstetricians and Gynecologists (ACOG) would improve overall outcomes in pregnant patients with diabetes. Eligible pregnant women with a diagnosis of gestational diabetes or Type 2 diabetes will be randomized into either routine care with glycemic targets as currently recommended by ADA and ACOG (control arm), or more aggressive care with lower glycemic targets that more closely resemble normoglycemia in pregnancy (intervention arm). The glycemic targets for the control arm will be defined as follows: fasting ≤95 mg/dL, pre-prandial ≤95 mg/dL, and 1-hour postprandial ≤140 mg/dL. The glycemic targets for the intervention arm will be defined as follows: fasting ≤80 mg/dL, pre-prandial ≤80 mg/dL, and 1-hour postprandial ≤110 mg/dL. The primary outcome will be a 250-gram difference in birth weight between the two study arms. Secondary maternal and neonatal outcomes of interest will also be compared between the two study arms.

Eligible women will be randomized at a 1:1 ratio (using block randomization) into either the control arm or the intervention arm. It is understood that study participants, physicians, and nurse-educators cannot be blinded to group allocation. The randomization process will proceed as follows. A primary randomization model assigning patients to the "New Target" versus the "Standard Target" will be created for the one center (LAC+USC), and permuted-block randomization with random allocation will be used. The investigators will be blinded to the block size. The generation of randomization codes will be performed using SAS statistical software, v. 9.3, Cary, NC. A validation test will be performed to assure that treatment balance is achieved within the entire study.

Patients in the control arm will be instructed to check blood sugars seven times per day: fasting, pre-prandial, and 1 hour after each meal. The glycemic targets for the control arm will be defined as follows: fasting ≤95 mg/dL, pre-prandial ≤95 mg/dL, and 1-hour postprandial ≤140 mg/dL (i.e. conventional targets). Patients who do not achieve glycemic goals with diet and exercise will be started on medical therapy (metformin or insulin) at the discretion of a maternal-fetal medicine subspecialist and endocrinologist.

Patients in the experimental arm will be instructed to check blood sugars seven times per day: fasting, pre-prandial, and 1 hour after each meal. The glycemic targets for the intervention arm will be defined as follows: fasting ≤80 mg/dL, pre-prandial ≤80 mg/dL, and 1-hour postprandial ≤110 mg/dL. Patients who do not achieve glycemic goals with diet and exercise will be started on medical therapy (metformin or insulin) at the discretion of a maternal-fetal medicine subspecialist and endocrinologist.

The intervention is glycemic targets that are lower than those currently recommended by ADA and ACOG: fasting ≤80 mg/dL, pre-prandial ≤80 mg/dL, and 1-hour postprandial ≤110 mg/dL instead of fasting ≤95 mg/dL, pre-prandial ≤95 mg/dL, and 1-hour postprandial ≤140 mg/dL.

Number of prenatal care visits in which an intervention for blood sugars was recommended (e.g. starting medication or changing medication dose)

Did the patient need diabetes medication (including oral agents and insulin) during antepartum period?

Was the patient ever admitted to antepartum service for any indication, including poorly-controlled diabetes or diabetes-related complication?

primary cesarean section, repeat cesarean section, vaginal delivery, vaginal delivery with vacuum, vaginal delivery with forceps

Neonatal hyperbilirubinemia (as defined in AAP 2004 Clinical Practice Guideline "Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation")

Inclusion Criteria: Pregnant women with a singleton gestation 18 years or older Diagnosis of gestational diabetes (prior to 34 weeks gestational age) or Type 2 diabetes Exclusion Criteria: Diagnosed with gestational diabetes at or beyond 34 weeks gestational age Type 1 diabetes Diabetic retinopathy Diabetic nephropathy Diabetic vasculopathy

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