Antenatal Late Preterm Steroids (ALPS): A Randomized Placebo-Controlled Trial

Inclusion Criteria: Singleton Pregnancy. A twin pregnancy reduced to singleton (either spontaneously ortherapeutically) before 14,0 weeks by project gestational age is acceptable Gestational age at randomization between 34,0 weeks and 36,5 weeks confirmed by studycriteria High probability of delivery in the late preterm period (any one of the following):

• Membrane rupture as defined by the occurrence of any two of the following: pooling offluid in the vaginal vault, positive Nitrazine test, ferning of vaginal fluid,positive AmniSure test; or any one of the following: indigo carmine pooling in thevagina after amnioinfustion, visible leakage of amniotic fluid from the cervix or
• Preterm labor with intact membranes. Preterm labor is defined as at least 6 regularuterine contractions in an observation period of no more than 60 minutes and at leastone of the following: cervix greater than or equal to 3cm dilated or at least 75%effaced or
• Planned delivery by induction of labor or cesarean section in no less than 24 hoursand no more than 7 days, as deemed necessary by the provider. An induction must bescheduled to start by 36,5 weeks at the latest, whereas a cesarean delivery must bescheduled by 36,6 weeks at the latest. Therefore the latest gestational age forrandomization is 36,4 weeks for a planned induction. The planned delivery may be forany indication, such as the following: prior myomectomy, prior classical cesarean,intrauterine growth restriction (IUGR), oligohydramnios, preeclampsia, nonreassuringfetal heart rate tracing warranting delivery, abruption, placenta previa

Exclusion Criteria:

1. Any prior antenatal corticosteroid course during the pregnancy because of potentialcontamination of the placebo group
2. Candidate for stress dose corticosteroids because of chronic steroid therapy toprevent suppression of adrenal gland, because of potential contamination of theplacebo group
3. Twin gestation reduced to a singleton gestation at or after 14 weeks 0 days by projectgestational age either spontaneously or therapeutically
4. Fetal demise, or known major fetal anomaly, including cardiac anomaly and hydrops
5. Maternal contraindication to betamethasone: hypersensitivity reaction to anycomponents of the medication, idiopathic thromboycytopenic purpura, systemal fungalinfection in case of exacerbation by betamethasone, use of amphotericin B due to thepossibility of heart failure with concomitant betamethasone
6. Pre-gestational diabetes - exclude if the patient was on medication (insulin,glyburide) prior to pregnancy
7. Delivery expected within 12 hours of randomization, because of insufficient time ofcorticosteroids to confer benefit, including any of the following: A. Rupture of Membranes (ROM) does not satisfy protocol criteria - exclude if thepatient being evaluated for Preterm Premature Rupture of Membranes (pPROM), does nothave preterm labor or planned delivery and does not satisfy the spontaneous membranerupture criteria (any 2 of: positive Nitrazine test, pooling of fluid in the vaginalvault test or ferning of vaginal fluid; or indigo carmine pooling in the vagina afteramnioinfusion; or visible leakage of amniotic fluid from the cervix) B. Rupture of themembranes in the presence of more than 6 contractions per hour or cervical dilation of 3 cm or more, unless oxytocin was withheld for at least 12 hours (other inductionagents allowed) C. Chorioamnionitis - exclude if patient is diagnosed withchorioamnionitis D. Cervical dilation ≥ 8 cm E. Evidence of non-reassuring fetalstatus requiring immediate delivery
8. Participation in another interventional study that influences neonatal morbidity andmortality
9. Participation in this trial in a previous pregnancy
10. Delivery at a non-network hospital
11. At 36, 0 weeks to 36, 5 weeks and quota for 36 weeks already met. To ensure there isan adequate proportion of women presenting at 34 to 35 weeks of gestation, enrollmentwill be restricted so that no more than 50% of the women in the trial present at 36weeks.