Estimated effect of 17 alpha-hydroxyprogesterone caproate on preterm birth in the United States.
OBJECTIVE
A multicenter, randomized placebo-controlled trial among women with singleton pregnancies and a history of spontaneous preterm birth found that weekly injections of 17 alpha-hydroxyprogesterone caproate (17P), initiated between 16 and 20 weeks of gestation, reduced preterm birth by 33%. The current study estimated both preterm birth recurrence and the potential reduction in the national preterm birth rate.


METHODS
Using 2002 national birth certificate data, augmented by vital statistics from 2 states, we estimated the number of singleton births delivered to women eligible for 17P through both a history of spontaneous preterm birth and prenatal care onset within the first 4 months of pregnancy. The number and rate of recurrent spontaneous preterm births were estimated. To predict effect, the reported 33% reduction in spontaneous preterm birth attributed to 17P therapy was applied to these estimates.


RESULTS
In 2002, approximately 30,000 recurrent preterm births occurred to women eligible for 17P, having had a recurrent preterm birth rate of 22.5%. If 17P therapy were delivered to these women, nearly 10,000 spontaneous preterm births would have been prevented, thereby reducing the overall United States preterm birth rate by approximately 2%, from 12.1% to 11.8% (P < .001), with higher reductions in targeted groups of eligible pregnant women.


CONCLUSIONS
Use of 17P could reduce preterm birth among eligible women, but would likely have a modest effect on the national preterm birth rate. Additional research is urgently needed to identify other populations who might benefit from 17P, evaluate new methods for early detection of women at risk, and develop additional prevention strategies.


METHODS
III.
Petrini
Joann R
JR
National Office, March of Dimes, 1275 Mamaroneck Avenue, White Plains, NY 10605, USA. jpetrini@marchofdimes.com
Callaghan
William M
WM
Klebanoff
Mark
M
Green
Nancy S
NS
Lackritz
Eve M
EM
Howse
Jennifer L
JL
Schwarz
Richard H
RH
Damus
Karla
K
D000077713:17 alpha-Hydroxyprogesterone Caproate; D000293:Adolescent; D000328:Adult; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D006908:Hydroxyprogesterones / Q000627:therapeutic use*; D015994:Incidence; D007273:Injections, Intramuscular; D008137:Longitudinal Studies; D011247:Pregnancy; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000453:epidemiology* / Q000517:prevention & control*; D011295:Prenatal Care / Q000379:methods; D011336:Probability; D012016:Reference Values; D018570:Risk Assessment; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
D006908:Hydroxyprogesterones; D000077713:17 alpha-Hydroxyprogesterone Caproate