ACOG Statement on 17p Hydroxyprogesterone Caproate

Washington, DC—Christopher M. Zahn, MD, vice president, Practice Activities of the American College of Obstetricians and Gynecologists (ACOG), issued the following statement regarding the findings of the PROLONG (Progestin’s Role in Optimizing Neonatal Gestation) trial, a randomized, double-blinded, placebo-controlled clinical trial evaluating 17-hydroxyprogesterone caproate (17p):

“ACOG’s clinical guidance, ‘Prediction and Prevention of Preterm Birth,’ details important information for ob-gyns caring for patients at risk for preterm birth, including risk factors, screening modalities, and the evidence around treatment interventions. After reviewing the findings from the PROLONG trial, ACOG finds that its current guidance will remain in effect.

“Consideration for offering 17p to women at risk of recurrent preterm birth should take into account the body of evidence for progesterone supplementation, the values and preferences of the pregnant woman, the resources available, and the setting in which the intervention will be implemented. Additional information from planned meta-analysis and secondary analyses will need to be evaluated to assess the impact this intervention has on women at risk of recurrent preterm birth in the United States.

“ACOG recognizes that the PROLONG clinical trial evaluating 17p in patients with a history of a prior spontaneous singleton preterm delivery, demonstrated no statistical difference in the co-primary outcome of preterm birth less than 35 0/7 weeks of gestation and neonatal composite index. Similarly, the rate of preterm birth less than 37 and less than 32 weeks were not different. No other differences in perinatal or maternal outcomes were detected. ACOG also understands that the authors suggest that the study was underpowered to assess treatment efficacy and that due to previous treatment guidelines, there may have been an unintentional selection bias.

“ACOG’s guidance is based on a review of the best available literature. As such, we will continue to monitor this topic, evaluate additional literature and any further analyses as published, and address findings as needed in relevant clinical guidance.

“It is well known that infants born prematurely have increased risks of poor outcomes, including death, and that the risk decreases as gestational age increases. In fact, preterm birth is the leading cause of neonatal mortality in the United States. Preventing preterm birth can help give babies a better chance at a healthy life.

“ACOG remains committed to providing ob-gyns and other women’s health care providers with evidence-based guidelines to help ensure the health and well-being of women and their families.”

The American College of Obstetricians and Gynecologists (ACOG) is the nation’s leading group of physicians providing health care for women. As a private, voluntary, nonprofit membership organization of more than 58,000 members, ACOG strongly advocates for quality health care for women, maintains the highest standards of clinical practice and continuing education of its members, promotes patient education, and increases awareness among its members and the public of the changing issues facing women’s health care. www.acog.org