17-OHPC to Prevent Recurrent Preterm Birth in Singleton Gestations (PROLONG Study): A Multicenter, International,...

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine
• Neonatology

Background:

• Women with a history of spontaneous preterm birth (SPTB) face a significantly higher risk of recurrent preterm birth (PTB).
• Previous research indicated a potential benefit of 17-alpha-hydroxyprogesterone caproate (17-OHPC) in reducing PTB, based on an early-terminated U.S. trial.

Purpose of the Study:

• To evaluate the efficacy of 17-alpha-hydroxyprogesterone caproate (17-OHPC) in decreasing recurrent preterm birth (PTB) in singleton gestations.
• To assess the impact of 17-OHPC on neonatal morbidity in women with a history of SPTB.

Main Methods:

• A double-blind, placebo-controlled international trial (NCT01004029) involving women with a prior singleton SPTB.
• Participants received weekly intramuscular injections of 250 mg 17-OHPC or placebo from 16 0/7 to 20 6/7 weeks gestation until delivery or 36 weeks.
• Co-primary outcomes included PTB < 35 weeks and a composite neonatal morbidity index; intention-to-treat analysis was performed.

Main Results:

• No significant difference in PTB < 35 weeks was observed between the 17-OHPC group (11.0%) and the placebo group (11.5%).
• The composite neonatal morbidity index also showed no significant difference (17-OHPC 5.6% vs. placebo 5.0%).
• Rates of fetal/early infant death were similar between groups (1.7% vs. 1.9%), with no increased risk associated with 17-OHPC.

Conclusions:

• 17-alpha-hydroxyprogesterone caproate (17-OHPC) did not demonstrate a significant effect in reducing recurrent preterm birth in this study population.
• The treatment was not associated with an increased risk of fetal or early infant death.
• Findings suggest that 17-OHPC may not be effective for preventing recurrent PTB in women with a history of SPTB.