While searching for an article to present for my journal club in July, I knew I wanted to talk about something new and relevant to my chosen field of Ob/Gyn. When I came across a recent article in the NEJM published by a group of Maternal-Fetal Medicine physicians, I was immediately intrigued. The article, titled “Antenatal betamethasone for women at risk of late preterm delivery”, is a double blind randomized control trial  (ALPS trial) that assessed if giving women antenatal steroids between 34.0-36.6 weeks gestation decreased neonatal respiratory complications. At the time, I thought this was a very relevant topic as I had just studied for Step 2 CK and encountered many questions that asked about when to give or not give steroids for lung maturity.  The answer for boards was always that before 34 weeks, give steroids, and after 34 weeks, don’t. 

This study aimed to shed some light on what to do about infants who are born in the late preterm period, between 34.0 weeks and 36.6 weeks. There previously had been little conclusive data regarding the benefits of antenatal corticosteroids for fetal lung maturity in this gray area. Study participants were randomized into a treatment group, who received 2 doses of betamethasone 24 hours apart, or a control group, who received 2 doses of a placebo 24 hours apart.  The primary outcome for the study was a composite result made up of several factors: the use of CPAP or high-flow nasal cannula for at least 2 hours, supplemental oxygen with an FiO2 of at least 0.3 for 4 hours, ECMO, or mechanical ventilation. There were several other secondary outcomes including rates of transient tachypnea of the newborn, bronchopulmonary dysplasia, and surfactant use. The study found that the primary composite outcomes occurred less frequently in the treatment group vs the control group (14.4% vs. 11.6%, RR 0.80, 95% CI 0.66 to 0.97, P=0.02). Several of the secondary outcomes occurred less frequently in the treatment group as well.

Very soon after this article was published, the American Congress of Obstetricians and Gynecologists (ACOG) released a practice advisory stating “administration of betamethasone may be considered in women with a singleton pregnancy between 34.0 and 36.6 weeks gestation at imminent risk of preterm birth within 7 days”. I found out first hand just how relevant this new data was on the first day of my OB sub-internship this month, when we had a patient at 35 weeks and 5 days and the attending turned to me and asked “have you heard of the ALPS trial?” Over the past 2 weeks, I’ve seen 3 patients in the late preterm period receive betamethasone based on the findings from this study. It’s pretty cool to see the positive impact of research on daily practice!

 

Article reference: Gyamfi-Bannerman C, Thom EA, Blackwell SC, Tita AT, Reddy UM, Saade GR, et al. Antenatal betamethasone for women at risk for late preterm delivery. NICHD Maternal-Fetal Medicine Units Network. N Engl J Med 2016; DOI: 10.1056/NEJMoa1516783. PMID: 26842679.

Kelly Guttman, MS4

Women's Health Pathway