1.1. Analysis.
Comparison 1 Betamimetic versus placebo/no treatment (primary outcomes), Outcome 1 Very preterm birth (Less than 34 weeks' gestation).
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.