title: Effect of partial compliance on the prevention of recurrent preterm birth in women receiving weekly 17 alpha-hydroxyprogesterone caproate injections.
abstract: OBJECTIVE
  To analyze the effect of partial compliance on preterm birth (PTB) prevention among women with previous PTB and receiving 17 alpha-hydroxyprogesterone caproate (17-OHPC).
  
  
  METHODS
  This is a secondary analysis of a multicenter trial for the prevention of recurrent PTB. Women with prior PTB were randomly assigned between 15 0/7 and 20 3/7 weeks to weekly injections of either 17-OHPC or placebo. Full 100% compliance (group 1) was compared to 40-80% (group 2). Recurrent PTB rates and odds ratios were calculated. Student's t, Chi-square, Wilcoxon Rank-Sum, multivariate logistic regression and Breslow-Day tests were used.
  
  
  RESULTS
  Group 1 included 370 women versus 35 in group 2. In each group, the PTB rate was significantly reduced in pregnancies receiving 17-OHPC compared to placebo. The adjusted odds ratio for PTB rate in group 1 was 0.48 (95% CI 0.31-0.75) versus 0.18 (95% CI 0.04-0.92) in group 2. Comparing the homogeneity of both odds ratios, the rates of recurrent PTB prevention in both groups were not statistically different (Breslow-Day test; p= .15).
  
  
  CONCLUSIONS
  A compliance rate of 40-80% did not significantly reduce 17-OHPC's efficacy. If confirmed, our findings could lead to a dramatic decrease in costs related to prevention of recurrent PTB.
authors.affiliation: a Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences , McGovern Medical School at The University of Texas Health Science Center, Houston (UTHealth) , Texas , USA.
authors.forename: Ziad A
authors.initials: ZA
authors.lastname: Haidar
authors.affiliation: a Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences , McGovern Medical School at The University of Texas Health Science Center, Houston (UTHealth) , Texas , USA.
authors.forename: Hind N
authors.initials: HN
authors.lastname: Moussa
authors.affiliation: a Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences , McGovern Medical School at The University of Texas Health Science Center, Houston (UTHealth) , Texas , USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Hosseini Nasab
authors.affiliation: a Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences , McGovern Medical School at The University of Texas Health Science Center, Houston (UTHealth) , Texas , USA.
authors.forename: Baha M
authors.initials: BM
authors.lastname: Sibai
mesh_terms: D000077713:17 alpha-Hydroxyprogesterone Caproate; D000328:Adult; D005260:Female; D005865:Gestational Age; D006801:Humans; D006908:Hydroxyprogesterones / Q000008:administration & dosage*; D007231:Infant, Newborn; D007273:Injections, Intramuscular; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology* / Q000517:prevention & control*; D012008:Recurrence; D016896:Treatment Outcome; D055815:Young Adult; D016903:Drug Monitoring
chemical_list: D006908:Hydroxyprogesterones; D000077713:17 alpha-Hydroxyprogesterone Caproate
keywords: Compliance; Recurrent preterm birth; hydroxyprogesterone caproate; prevention; progesterone