Vaginal Progesterone
to Prevent
Preterm Birth
in High-Risk Women
Abstract Preterm birth is a signifi cant problem in the United States, contributing to neonatal morbidity and mortality.
Progesterone is a hormone naturally produced by the corpus luteum and the placenta in early pregnancy and is essential for
maintaining pregnancy. Clinicians and researchers have used this hormone in later gestation to try to prevent preterm birth.
However, mechanisms of action, indications for use, dosing and administration have varied and are not fully understood.
Th is article revisits two recent randomized controlled trials in which researchers investigated the eff ectiveness of vaginal
progesterone suppositories and gel in the prevention of preterm birth among women who were at high risk for delivering
prematurely.