Confirmatory Study of 17P vs Vehicle for Prevention of Preterm Birth in Women w/ Previous Spontaneous Preterm Delivery

One of the most significant risk factors for preterm birth is previous pregnancy history. Women who have had a prior preterm birth have a 2.5-fold greater risk than women with no prior history of preterm birth. Prophylactic methods for prevention of preterm birth, including tocolytic drugs, bed rest, and other interventions such as cerclage, have been shown in most studies to be ineffective. One of the preventive measures that has shown effectiveness in randomized trials is the use of progesterone agents.9,10 Progesterone has been shown to support gestation and to inhibit uterine activity.