title: Does progesterone treatment influence risk factors for recurrent preterm delivery?
abstract: OBJECTIVE
  To examine how demographic and pregnancy characteristics can affect the risk of recurrent preterm delivery and the how the effectiveness of progesterone treatment for prevention alters these relationships.
  
  
  METHODS
  This was a secondary analysis of a randomized trial of 17alpha-hydroxyprogesterone caproate to prevent recurrent preterm delivery in women at risk. Associations of risk factors for preterm delivery (less than 37 completed weeks of gestation) were examined separately for the women in the 17alpha-hydroxyprogesterone caproate (n = 310) and placebo (n = 153) groups.
  
  
  RESULTS
  Univariate analysis found that the number of previous preterm deliveries and whether the penultimate delivery was preterm were significant risk factors for preterm delivery in both the placebo and progesterone groups. High body mass index was protective of preterm birth in the placebo group. Multivariate analysis found progesterone treatment to cancel the risk of more than 1 previous preterm delivery, but not the risk associated with the penultimate pregnancy delivered preterm. Obesity was associated with lower risk for preterm delivery in the placebo group but not in the women treated with progesterone.
  
  
  CONCLUSIONS
  The use of 17alpha-hydroxyprogesterone caproate in women with a previous preterm delivery reduces the overall risk of preterm delivery and changes the epidemiology of risk factors for recurrent preterm delivery. In particular, these data suggest that 17alpha-hydroxyprogesterone caproate reduces the risk of a history of more than 1 preterm delivery.
  
  
  METHODS
  I.
authors.affiliation: National Institute of Child Health and Human Development, Rockville, Maryland, USA. pmeis@wfubmc.edu
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Meis
authors.forename: Mark
authors.initials: M
authors.lastname: Klebanoff
authors.forename: Mitchell P
authors.initials: MP
authors.lastname: Dombrowski
authors.forename: Baha M
authors.initials: BM
authors.lastname: Sibai
authors.forename: Sharon
authors.initials: S
authors.lastname: Leindecker
authors.forename: Atef H
authors.initials: AH
authors.lastname: Moawad
authors.forename: Allison
authors.initials: A
authors.lastname: Northen
authors.forename: Jay D
authors.initials: JD
authors.lastname: Iams
authors.forename: Michael W
authors.initials: MW
authors.lastname: Varner
authors.forename: Steve N
authors.initials: SN
authors.lastname: Caritis
authors.forename: Mary J
authors.initials: MJ
authors.lastname: O'Sullivan
authors.forename: Menachem
authors.initials: M
authors.lastname: Miodovnik
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Leveno
authors.forename: Deborah
authors.initials: D
authors.lastname: Conway
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Wapner
authors.forename: Marshall
authors.initials: M
authors.lastname: Carpenter
authors.forename: Brian
authors.initials: B
authors.lastname: Mercer
authors.forename: Susan M
authors.initials: SM
authors.lastname: Ramin
authors.forename: John M
authors.initials: JM
authors.lastname: Thorp
authors.forename: Alan M
authors.initials: AM
authors.lastname: Peaceman
authors.forename: Steven
authors.initials: S
authors.lastname: Gabbe
mesh_terms: D000077713:17 alpha-Hydroxyprogesterone Caproate; D000328:Adult; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000627:therapeutic use*; D015999:Multivariate Analysis; D007752:Obstetric Labor, Premature / Q000453:epidemiology / Q000517:prevention & control*; D011247:Pregnancy; D011372:Progestins / Q000627:therapeutic use*; D012008:Recurrence; D012307:Risk Factors
chemical_list: D006908:Hydroxyprogesterones; D011372:Progestins; D000077713:17 alpha-Hydroxyprogesterone Caproate