Glycemic Observation and Metabolic Outcomes in Mothers and Offspring

Primary outcome in GO MOMs mothers: Number of mothers diagnosed with gestational diabetes mellitus (GDM) using a 100 g 3 hr OGTT at 24w0d-28w0d gestation according to Carpenter-Coustan criteria (at least two of the timed glucose measurements greater than or equal to the following thresholds: fasting >= 95 mg/dL, 1 hr >= 180 mg/dL, 2 hr >= 155 mg/dL, 3 hr >= 140 mg/dL).

Primary outcome in GO MOMs newborns: Number of newborns who are large for gestational age (LGA), defined as birthweight >90th percentile for gestational age according to Aris et al. (2019). The first birthweight after delivery obtained from medical chart abstraction will be used for defining the primary LGA outcome.

Secondary outcome in GO MOMs mothers: Number of mothers with hypertensive disorders of pregnancy including preeclampsia with and without severe features, gestational hypertension, eclampsia, and Hemolysis, Elevated Liver enzymes, and Low Platelet count (HELLP) syndrome, defined by the American College of Obstetricians and Gynecologists (ACOG) criteria

Secondary outcome in GO MOMs mothers: Number of mothers with cesarean delivery

Secondary outcome in GO MOMs newborns: Newborn sum of flank, triceps, and subscapular skinfolds, evaluated as a continuous measure and dichotomized as >90th percentile.

Secondary outcome in GO MOMs newborns: Number of newborns who are small for gestational age (SGA), defined as birthweight < 10th percentile for gestational age according to Aris et al. (2019)

Secondary outcome in GO MOMs newborns: Number of newborns with preterm birth, defined as delivery prior to estimated gestational age 37 weeks 0 days.

Secondary outcome in GO MOMs newborns: Number of newborns with shoulder dystocia, identified through chart abstraction and defined clinically, requiring documentation that providers applied maneuvers to reduce the shoulder at delivery.

Secondary outcome in GO MOMs newborns: Number of newborns with neonatal birth injury, identified through chart abstraction and defined as brachial plexus palsy or clavicular, humeral, or skull fracture.

Secondary outcome in GO MOMs newborns: Number of newborns with neonatal hypoglycemia, identified through chart abstraction and defined as treated neonatal hypoglycemia.

Secondary outcome in GO MOMs newborns: Number of newborns with neonatal respiratory morbidity, identified through chart abstraction and defined as need for respiratory support within 72 hrs after birth and consisting of one or more of the following: the use of continuous positive airway pressure (CPAP) or high-flow nasal cannula for at least 2 consecutive hrs, supplemental oxygen with a fraction of inspired oxygen of at least 0.30 for at least 4 continuous hrs, extracorporeal membrane oxygenation (ECMO), or mechanical ventilation. A high flow of air or blended air and oxygen is defined as more than 1 liter per minute

Secondary outcome in GO MOMs newborns: Number of newborns with neonatal hyperbilirubinemia, identified through chart abstraction and defined as treatment of hyperbilirubinemia in the first week of life with phototherapy or exchange transfusion or a diagnosis of kernicterus.

Outcome in mothers for Nutrition Substudy: Mean CGM glucose at 24-28 weeks' gestation in mothers

Secondary outcome in mothers for Nutrition Substudy: Percent time above various glycemic thresholds: 100 miligrams/deciliter, 105 miligrams/deciliter, 110 miligrams/deciliter, 120 miligrams/deciliter, 140 miligrams/deciliter, as measured by continuous glucose monitor at 24-28 weeks' gestation.

Secondary outcome in mothers for Nutrition Substudy: Mean nocturnal glucose (12am-6am) in miligrams/deciliter, as measured by continuous glucose monitor at 24-28 weeks' gestation.

Secondary outcome in mothers for Nutrition Substudy: Maternal continuous glucose monitor-assessed glucose defined as percent time above various glycemic thresholds: 100 miligrams/deciliter, 105 miligrams/deciliter, 110 miligrams/deciliter, 120 miligrams/deciliter, 140 miligrams/deciliter, as measured by continuous glucose monitor at 16-20, 24-28, and 32-36 weeks' gestation.

Secondary outcome in mothers for Nutrition Substudy: Insulin resistance, as estimated by the Matsuda index quantified during the oral glucose tolerance test at 24-28 weeks' gestation. The Matsuda index calculates whole body insulin resistance, with insulin resistance defined as being equal to or lower than 2.5.

Secondary outcome in mothers for Nutrition Substudy: Insulin secretory response, as estimated by the ratio of insulin area under the curve to glucose area under the curve, during oral glucose tolerance test at 24-28 weeks' gestation.

Secondary outcome in mothers for Nutrition Substudy: Gestational diabetes mellitus, diagnosed using Carpenter-Coustan criteria applied to an oral glucose tolerance test at 24-28 weeks' gestation.

Secondary outcome in newborns for Nutrition Substudy: Neonatal fat mass as estimated by flank skinfold, measured as percent body fat, within 72 hours of delivery.

Secondary outcome in newborns for Nutrition Substudy: Large for gestational age birth weight defined as birth weight > 90th percentile for gestational age.

Secondary outcome for newborns for Nutrition Substudy: Birthweight for gestational age percentile. The first weight after delivery from the medical record will be used for defining this outcome.

Exploratory outcome in GO MOMs newborns: Number of newborns with neonatal intensive care unit (NICU) admissions

Exploratory outcome in GO MOMs newborns: Length of admission/length of stay (for NICU or entire delivery hospitalization) for newborns

Exploratory outcome in GO MOMs mothers: Spontaneous abortion (< 20 weeks of gestation)

Exploratory outcome in GO MOMs newborns: Number of mothers with stillbirth (intrauterine fetal demise at 20 weeks of gestation or later)

Exploratory outcome in GO MOMs newborns: Number of newborns with neonatal death

Exploratory outcome in GO MOMs newborns: Number of newborns with major congenital malformation

Exploratory outcome in GO MOMs mothers: Number of mothers with antepartum admissions or maternal readmissions

Exploratory outcome in GO MOMs newborns: Number of newborns with Apgar score <7 at 5 minutes

Exploratory outcome in mothers for Nutrition Substudy: Maternal fasting triglycerides as measured in miligrams/deciliter at 24-28 weeks' gestation.

Exploratory outcome in mothers for Nutrition Substudy: Maternal fasting free fatty acids as measured in millimoles per liter at 24-28 weeks' gestation.