title: 17 alpha-hydroxyprogesterone caproate to prevent prematurity in nulliparas with cervical length less than 30 mm.
abstract: OBJECTIVE
  We sought to evaluate whether 17 alpha-hydroxyprogesterone caproate (17-OHP) reduces preterm birth (PTB) in nulliparous women with a midtrimester cervical length (CL) <30 mm.
  
  
  METHODS
  In this multicenter randomized controlled trial, nulliparous women with a singleton gestation between 16 and 22 3/7 weeks with an endovaginal CL <30 mm (<10th percentile in this population) were randomized to weekly intramuscular 17-OHP (250 mg) or placebo through 36 weeks. The primary outcome was PTB <37 weeks.
  
  
  RESULTS
  The frequency of PTB did not differ between the 17-OHP (n = 327) and placebo (n = 330) groups (25.1% vs 24.2%; relative risk, 1.03; 95% confidence interval, 0.79-1.35). There also was no difference in the composite adverse neonatal outcome (7.0% vs 9.1%; relative risk, 0.77; 95% confidence interval, 0.46-1.30).
  
  
  CONCLUSIONS
  Weekly 17-OHP does not reduce the frequency of PTB in nulliparous women with a midtrimester CL <30 mm.
authors.affiliation: Northwestern University, Chicago, IL, USA.
authors.forename: William A
authors.initials: WA
authors.lastname: Grobman
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Thom
authors.forename: Catherine Y
authors.initials: CY
authors.lastname: Spong
authors.forename: Jay D
authors.initials: JD
authors.lastname: Iams
authors.forename: George R
authors.initials: GR
authors.lastname: Saade
authors.forename: Brian M
authors.initials: BM
authors.lastname: Mercer
authors.forename: Alan T N
authors.initials: AT
authors.lastname: Tita
authors.forename: Dwight J
authors.initials: DJ
authors.lastname: Rouse
authors.forename: Yoram
authors.initials: Y
authors.lastname: Sorokin
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Wapner
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Leveno
authors.forename: Sean
authors.initials: S
authors.lastname: Blackwell
authors.forename: M Sean
authors.initials: MS
authors.lastname: Esplin
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Tolosa
authors.forename: John M
authors.initials: JM
authors.lastname: Thorp
authors.forename: Steve N
authors.initials: SN
authors.lastname: Caritis
authors.forename: J Peter
authors.initials: JP
authors.lastname: Van Dorsten
mesh_terms: D000077713:17 alpha-Hydroxyprogesterone Caproate; D000293:Adolescent; D000328:Adult; D054791:Cervical Length Measurement / Q000187:drug effects*; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000627:therapeutic use*; D007231:Infant, Newborn; D007234:Infant, Premature; D010298:Parity / Q000187:drug effects*; D011247:Pregnancy; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000517:prevention & control*; D011372:Progestins / Q000627:therapeutic use*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D006908:Hydroxyprogesterones; D011372:Progestins; D000077713:17 alpha-Hydroxyprogesterone Caproate