About 17Alpha Hydroxyprogesterone Caproate (17P)
Premature delivery continues to increase in the United States and now exceeds 13% of all pregnancies.1 It is the leading cause of infant mortality in North Carolina, as 
well as the single leading cause of cerebral palsy. In North Carolina each year over 16,000 babies are born too soon. Medicaid costs for hospital intensive care for these babies totals over $120 million annually.
Health care providers do not have many tools to use once preterm labor has begun. Tocolytic therapy (terbutaline, ritodrine, indomethacin, magnesium sulfate) has proven to have only minimal impact on preventing preterm delivery. At best, delivery can be delayed for 48 hours allowing for the administration of antenatal steroids to enhance fetal lung maturity. Even the prolonged use of oral tocolytics has not proven effective in averting premature delivery.
Without the ability to stop preterm labor, health care providers continue to look to ways to prevent preterm labor in the first place. Two studies point to prevention as a more optimal approach than treatment once the problem of premature contractions have begun. In 2003, Meis et al.2 reported that the weekly injection of 250 mg of a naturally occurring progesterone (17-hydroxyprogesterone) could result in a 33% reduction in the rate of preterm delivery prior to 35 weeks’ gestation and a 42% reduction prior to 32 weeks’ gestation. This study was the first to demonstrate a decrease in morbidity in the NICU – significantly lower rates of necrotizing enterocolitis, intraventricular hemorrhage and the need for supplemental oxygen. In a second randomized study from Brazil, a daily 100 mg progesterone vaginal suppository decreased the incidence of preterm delivery from 28.5% (placebo group) to 13.8%. Delivery prior to 34 weeks’ gestation was reduced from 18.5% to 2.7%.3
The exact mechanism by which progesterone prevents preterm birth is unknown although it is has been shown to decrease inflammation and blocks the effect of oxytocin on the myometrium, keeping the uterus from contracting. Studies to date have demonstrated that hydroxyprogesterone is not associated with congenital anomalies or other neonatal developmental problems.
An important feature of both recently reported studies is that enrollment was limited to singleton gestations in patients with a previous history of spontaneous preterm delivery. Studies to date have indicated that progesterone is not effective in preventing premature delivery in pregnancies at low risk for prematurity, multiple gestations, or in patients once preterm contractions have occurred.
Current candidates for progesterone should meet the following criteria:
- Singleton pregnancy
- Previous spontaneous preterm delivery (< 37 weeks gestation) of a single baby
A preferred use of progesterone is weekly intramuscular injections of 250 mg of 17-hydroxyprogesterone ideally starting at 16 weeks gestation and continuing to 36 weeks and 6 days.
Online Video About 17P
The 17P Project has developed a 13 minute educational video about reducing the risk of recurring preterm birth. The video features comments from mothers who have taken 17P as well as detailed information from physicians about the use of this medication.
To view this video online, please click here. To view the video full screen on your computer click on the real player button. Having problems? Give us a call at 919-843-7865 or 919-843-7864.
References
- Meis PJ. 17 hydroxyprogesterone for the prevention of preterm delivery. Obstet Gynecol 2005;105:1128-35.
- Meis PJ, Klebanoff M, Thom E, Dombrowski MP, Sibai B, Moawad Ah, et al. Prevention of recurrent preterm delivery by 17 alpha-hydroxyprogesterone caproate. N Eng J Med 2003;348:2379-85.
- da Fonseca EB, Bittar RE, Carvalho MH, Zugaub M. Prophylactic administration of progesterone by vaginal suppository to reduce the incidence of spontaneous preterm birth in women at increased risk: A randomized placebo-controlled double-blind study. Am J Obstet Gynecol 2003;188:419-24.
