title: A randomized controlled trial of intramuscular versus vaginal progesterone for the prevention of recurrent preterm birth.
abstract: OBJECTIVE
  To compare the efficacy of intramuscular hydroxyprogesterone caproate with that of vaginal progesterone for prevention of recurrent preterm birth.
  
  
  METHODS
  A prospective randomized controlled trial was conducted at a US tertiary care center between June 1, 2007, and April 30, 2010. Women with singleton pregnancies (16-20 weeks) and a history of spontaneous preterm birth were randomly allocated using a computer-generated randomization sequence to receive either a weekly intramuscular injection of hydroxyprogesterone caproate (250 mg) or a daily vaginal progesterone suppository (100 mg). Participants, investigators, and assessors were not masked to group assignment. The primary outcome was birth before 37 weeks of pregnancy. Per-protocol analyses were performed: participants who completed follow-up were included.
  
  
  RESULTS
  Analyses included 66 women given intramuscular progesterone and 79 given vaginal progesterone. Delivery before 37 weeks was recorded among 29 (43.9%) women in the intramuscular progesterone group and 30 (37.9%) in the vaginal progesterone group (P=0.50).
  
  
  CONCLUSIONS
  Weekly intramuscular administration of hydroxyprogesterone caproate and daily vaginal administration of a progesterone suppository exhibited similar efficacy in reducing the rate of recurrent preterm birth. ClinicalTrials.gov: NCT00579553.
authors.affiliation: Department of Obstetrics and Gynecology, New York Medical College, Westchester Medical Center, Valhalla, NY, USA. Electronic address: elimiana@wcmc.com.
authors.forename: Andrew
authors.initials: A
authors.lastname: Elimian
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
authors.forename: Katie
authors.initials: K
authors.lastname: Smith
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
authors.forename: Marvin
authors.initials: M
authors.lastname: Williams
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Knudtson
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
authors.forename: Jean R
authors.initials: JR
authors.lastname: Goodman
authors.affiliation: Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
authors.forename: Marilyn B
authors.initials: MB
authors.lastname: Escobedo
mesh_terms: D000077713:17 alpha-Hydroxyprogesterone Caproate; D000282:Administration, Intravaginal; D000328:Adult; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000008:administration & dosage*; D007231:Infant, Newborn; D007273:Injections, Intramuscular; D011247:Pregnancy; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000517:prevention & control*; D011372:Progestins / Q000008:administration & dosage*; D011446:Prospective Studies; D062606:Tertiary Care Centers; D014481:United States; D055815:Young Adult
chemical_list: D006908:Hydroxyprogesterones; D011372:Progestins; D000077713:17 alpha-Hydroxyprogesterone Caproate
keywords: Preterm birth; Prevention; Progesterone