title: Outcome of the Vaginal Infections and Prematurity Study: results of a clinical trial of erythromycin among pregnant women colonized with group B streptococci.
abstract: OBJECTIVE
  Our purpose was to determine whether erythromycin treatment of pregnant women colonized with group B streptococci would reduce the occurrence of low birth weight (< 2500 gm) and preterm (< 37 completed weeks) birth.
  
  
  METHODS
  In a double-blind clinical trial, 938 carriers of group B streptococci were randomized to receive erythromycin base (333 mg three times a day) or matching placebo beginning during the third trimester and before 30 weeks and continuing for 10 weeks or until 35 weeks 6 days of pregnancy.
  
  
  RESULTS
  Pregnancy outcomes were available for 97% of randomized women; 14% of subjects withdrew from the trial. Birth weight < 2500 gm occurred in 8.6% of the erythromycin and 6.1% of the placebo recipients (relative risk 1.4, 0.9 to 2.2, p = 0.16). Preterm delivery occurred in 11.4% of women randomized to erythromycin and in 12.3% randomized to placebo (relative risk 0.9, 95% confidence limits 0.6 to 1.3, p = 0.65). Greater benefit of erythromycin in reducing these outcomes was not observed among women reporting the best compliance.
  
  
  CONCLUSIONS
  In this study of pregnant women colonized with group B streptococci treatment with erythromycin was not shown to be effective at prolonging gestation or reducing low birth weight. Greater than anticipated complicating factors, including spontaneous clearance of the organism, use of nontrial antibiotics, and density of colonization, may have resulted in population sizes too small to detect a benefit of treatment. Future studies should take these factors into account in determining sample sizes.
authors.affiliation: National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Klebanoff
authors.forename: J A
authors.initials: JA
authors.lastname: Regan
authors.forename: A V
authors.initials: AV
authors.lastname: Rao
authors.forename: R P
authors.initials: RP
authors.lastname: Nugent
authors.forename: W C
authors.initials: WC
authors.lastname: Blackwelder
authors.forename: D A
authors.initials: DA
authors.lastname: Eschenbach
authors.forename: J G
authors.initials: JG
authors.lastname: Pastorek
authors.forename: S
authors.initials: S
authors.lastname: Williams
authors.forename: R S
authors.initials: RS
authors.lastname: Gibbs
authors.forename: J C
authors.initials: JC
authors.lastname: Carey
mesh_terms: D000328:Adult; D001724:Birth Weight; D004311:Double-Blind Method; D004917:Erythromycin / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D007752:Obstetric Labor, Premature / Q000517:prevention & control*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy* / Q000382:microbiology; D011256:Pregnancy Outcome; D013290:Streptococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D013292:Streptococcus agalactiae / Q000302:isolation & purification; D014481:United States; D014621:Vagina / Q000382:microbiology*; D016585:Vaginosis, Bacterial / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D004917:Erythromycin