Analysis 5.1.
Comparison 5 Vaginal progesterone versus placebo: multiple pregnancy and another risk factor, Outcome 1 Preterm birth less than 34 weeks.
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.