title: Meta-analysis of randomized controlled trials comparing 17α-hydroxyprogesterone caproate and vaginal progesterone for the prevention of recurrent spontaneous preterm delivery.
abstract: BACKGROUND
  Vaginal progesterone and 17α-hydroxyprogesterone (17α-OHP) are both used to prevent preterm delivery in women who have experienced spontaneous preterm delivery (SPTD) previously. Randomized trial data of the comparative effectiveness of these interventions have been mixed.
  
  
  OBJECTIVE
  To compare the efficacy of intramuscular 17α-OHP and vaginal progesterone in the prevention of recurrent SPTD.
  
  
  METHODS
  Cochrane Central Register of Controlled Trials, African Journals Online, Embase, Google Scholar, ISI Web of Science, LILACS, CINAHL, PubMed, and registers of ongoing trials were searched using keywords related to 17α-OHP, vaginal progesterone, and preterm delivery.
  
  
  METHODS
  Randomized controlled trials published between January 1, 1966, and November 30, 2016, comparing 17α-OHP and vaginal progesterone for the prevention of recurrent SPTD during singleton pregnancies were included.
  
  
  METHODS
  Study data were extracted and meta-analyses were performed when outcomes were comparable.
  
  
  RESULTS
  The meta-analyses included data from three randomized trials. Lower rates of SPTD before 34 weeks (relative risk 0.71, 95% confidence interval 0.53-0.95) and before 32 weeks (relative risk 0.62, 95% confidence interval 0.40-0.94) of pregnancy were observed among patients treated with vaginal progesterone.
  
  
  CONCLUSIONS
  Vaginal progesterone and 17α-OHP were comparable for the prevention of recurrent SPTD in singleton pregnancies; vaginal progesterone could be superior.
authors.affiliation: Department of Obstetrics and Gynecology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Oler
authors.affiliation: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Ahizechukwu C
authors.initials: AC
authors.lastname: Eke
authors.affiliation: Department of Obstetrics and Gynecology, University of Michigan School of Medicine, Ann Arbor, MI, USA.
authors.forename: Ashley
authors.initials: A
authors.lastname: Hesson
mesh_terms: D000077713:17 alpha-Hydroxyprogesterone Caproate; D000282:Administration, Intravaginal; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000008:administration & dosage*; D007273:Injections, Intramuscular; D011247:Pregnancy; D047928:Premature Birth / Q000517:prevention & control*; D011374:Progesterone / Q000008:administration & dosage*; D011372:Progestins / Q000008:administration & dosage*; D016032:Randomized Controlled Trials as Topic; D012008:Recurrence
chemical_list: D006908:Hydroxyprogesterones; D011372:Progestins; D000077713:17 alpha-Hydroxyprogesterone Caproate; D011374:Progesterone
keywords: 17 alpha progesterone; Preterm labor; Recurrent preterm delivery; Vaginal progesterone