The lead presentation at the SMFM Annual Meeting in February of 2016 was an evaluation of the benefit of antenatal betamethasone therapy in patients at risk of delivering in the late preterm period (34 0/7-36 6/7 weeks).(1) It was concurrently published in the NEJM. The study was a multicenter, randomized control trial by the NICHD MFMU Network, and the results created quite a buzz. The primary outcome of the study was a neonatal composite end point of 1) indicators of significant respiratory support 2) stillbirth, and 3) neonatal death within 72 hours. The study suggested a statistically significantly lower composite outcome in the group treated with betamethasone compared to placebo (11.6% vs. 14.4%, relative risk 0.80, 95% CI 0.66-0.97, P=0.02). These findings suggest a benefit of administering antenatal corticosteroids (ACS) to patients at risk for preterm birth after 34 weeks – the current recommended upper limit for ACS therapy.
We are currently reviewing the inclusion criteria for the study to determine which patients are appropriate candidates (there were a number of patients excluded) and how they should be managed during the 48 hour steroid window. For example, do we delay delivery for the patient with severe preeclampsia or give tocolytic agents to the patient in preterm labor? Once determined, an implementation plan will be communicated. Please stay tuned. Until then, we advocate the current standard of care: ACS administration between 24 to 34 weeks’ gestation.
If you have questions, please feel free to contact one of the MFMs at Northwest Perinatal Center.
References
1. 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. NEJM. February 4, 2016; DOI: 10.1056/NEJMoa1516783
