title: Removal versus retention of cerclage in preterm premature rupture of membranes: a randomized controlled trial.
abstract: OBJECTIVE
  The decision of whether to retain or remove a previously placed cervical cerclage in women who subsequently rupture fetal membranes in a premature gestation is controversial and all studies to date are retrospective. We performed a multicenter randomized controlled trial of removal vs retention of cerclage in these patients to determine whether leaving the cerclage in place prolonged gestation and/or increased the risk of maternal or fetal infection.
  
  
  METHODS
  A prospective randomized multicenter trial of 27 hospitals was performed. Patients included were those with cerclage placement at ≤23 weeks 6 days in singleton or twin pregnancies, with subsequent spontaneous rupture of membranes between 22 weeks 0 days and 32 weeks 6 days. Patients were randomized to retention or removal of cerclage. Patients were then expectantly managed and delivered only for evidence of labor, chorioamnionitis, fetal distress, or other medical or obstetrical indications. Management after 34 weeks was at the clinician's discretion.
  
  
  RESULTS
  The initial sample size calculation determined that a total of 142 patients should be included but after a second interim analysis, futility calculations determined that the conditional power for showing statistical significance after randomizing 142 patients for the primary outcome of prolonging pregnancy was 22.8%. Thus the study was terminated after a total of 56 subjects were randomized with complete data available for analysis, 32 to removal and 24 to retention of cerclage. There was no statistical significance in primary outcome of prolonging pregnancy by 1 week comparing the 2 groups (removal 18/32, 56.3%; retention 11/24, 45.8%) P = .59; or chorioamnionitis (removal 8/32, 25.0%; retention 10/24, 41.7%) P = .25, respectively. There was no statistical difference in composite neonatal outcomes (removal 16/33, 50%; retention 17/30, 56%), fetal/neonatal death (removal 4/33, 12%; retention 5/30, 16%); or gestational age at delivery (removal mean 200 days; retention mean 198 days).
  
  
  CONCLUSIONS
  Statistically significant differences were not seen in prolongation of latency, infection, or composite neonatal outcomes. However, there was a numerical trend in the direction of less infectious morbidity, with immediate removal of cerclage. These findings may not have met statistical significance if the original sample size of 142 was obtained, however they provide valuable data suggesting that there may be no advantage to retaining a cerclage after preterm premature rupture of membranes and a possibility of increased infection with cerclage retention.
authors.affiliation: Long Beach Memorial Medical Center, Long Beach, and Kaiser Permanente, Anaheim, CA.
authors.forename: Anna
authors.initials: A
authors.lastname: Galyean
authors.affiliation: University of California Irvine, Orange, CA; Obstetrix/Pediatrix Medical Group, Sunrise, FL.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Garite
authors.affiliation: Obstetrix/Pediatrix Medical Group, Sunrise, FL.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Maurel
authors.affiliation: Obstetrix/Pediatrix Medical Group, Sunrise, FL.
authors.forename: Diana
authors.initials: D
authors.lastname: Abril
authors.affiliation: Regional Obstetrical Consultants and University of Tennessee, Chattanooga, TN.
authors.forename: Charles D
authors.initials: CD
authors.lastname: Adair
authors.affiliation: Obstetrix Medical Group of Georgia, Decatur, GA.
authors.forename: Paul
authors.initials: P
authors.lastname: Browne
authors.affiliation: Obstetrix Medical Group, San Jose, CA.
authors.forename: C Andrew
authors.initials: CA
authors.lastname: Combs
authors.affiliation: University of Cincinnati, Cincinnati, OH, and Norton Healthcare, Kosair Maternal-Fetal Medicine, Louisville, KY.
authors.forename: Helen
authors.initials: H
authors.lastname: How
authors.affiliation: High Risk Pregnancy Center, Las Vegas, NV.
authors.forename: Brian K
authors.initials: BK
authors.lastname: Iriye
authors.affiliation: University of Illinois at Chicago, Chicago, IL.
authors.forename: Michelle
authors.initials: M
authors.lastname: Kominiarek
authors.affiliation: Obstetrix Medical Group, Kansas City, MO.
authors.forename: George
authors.initials: G
authors.lastname: Lu
authors.affiliation: Obstetrix Medical Group, Seattle, WA.
authors.forename: David
authors.initials: D
authors.lastname: Luthy
authors.affiliation: Obstetrix Medical Group, Tucson, AZ.
authors.forename: Hugh
authors.initials: H
authors.lastname: Miller
authors.affiliation: Long Beach Memorial Medical Center, Long Beach, and Kaiser Permanente, Anaheim, CA.
authors.forename: Michael
authors.initials: M
authors.lastname: Nageotte
authors.affiliation: University of Rochester, Rochester, NY.
authors.forename: Tulin
authors.initials: T
authors.lastname: Ozcan
authors.affiliation: University of California Irvine, Orange, CA.
authors.forename: Manuel
authors.initials: M
authors.lastname: Porto
authors.affiliation: Memorial Hermann Hospital, Houston, TX.
authors.forename: Mildred
authors.initials: M
authors.lastname: Ramirez
authors.affiliation: Obstetrix Medical Group, Phoenix, AZ.
authors.forename: Shirley
authors.initials: S
authors.lastname: Sawai
authors.affiliation: Wayne State University, Detroit, MI.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Sorokin
mesh_terms: D000328:Adult; D023802:Cerclage, Cervical / Q000009:adverse effects; D002821:Chorioamnionitis / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000628:therapy*; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth / Q000517:prevention & control*; D016896:Treatment Outcome
keywords: cerclage; chorioamnionitis; latency; preterm premature rupture of membranes