Continuous Glucose Monitoring of Late Preterm Birth After Corticosteroids

Inclusion Criteria: * Pregnancy admitted to labor and delivery between 34w0d and 36w5d * English speaking women * High probability of delivery in late preterm period defined by any of the following: 1. Membrane rupture by 2 criteria (pooling, positive nitrazine, or ferning) OR leaking amniotic fluid from the cervix 2. Preterm labor with intact membrane, defined as at least 6 uterine contractions in 60 minutes and at least: cervical dilation greater than or equal to 3cm dilated OR 80% effaced OR planned delivery by induction of labor or cesarean in no less than 24 hrs and no more than 7 days, for any indication as deemed necessary by the provider * Received at least one dose of corticosteroid within twelve hours of enrollment Exclusion Criteria: * Any prior antenatal corticosteroid course in current pregnancy * Systemic corticosteroid administration during current pregnancy * Fetal demise or known major fetal anomaly, including cardiac anomaly or hydrops * Maternal contraindication to betamethasone: hypersensitivity reaction to any component of the medication, idiopathic thrombocytopenic, purpura, systemic fungal infection, or current use of amphotericin B * Diabetes, pregestational or gestational * Preexisting plan for intrapartum monitoring of maternal glucose levels for any reason * Delivery expected within 12 hours of randomization, because of insufficient time for corticosteroids to confer benefit, including: 1. Ruptured membranes with cervical dilation ≥ 3cm or with more than 6 contractions per hour unless Pitocin is deferred for at least 12 hours 2. Chorioamnionitis 3. Cervical dilation ≥ 8cm 4. Evidence of non-reassuring fetal status requiring immediate delivery * To ensure that there is an adequate proportion of women presenting at 34 to 35 weeks gestation, enrollment will be restricted so that no more than 50% of the women in the trial present at 36 weeks.