title: Recolonization of group B Streptococcus (GBS) in women with prior GBS genital colonization in pregnancy.
abstract: OBJECTIVE
  The purpose of the study is to evaluate the incidence of women with prior GBS genital colonization who have recolonization in subsequent pregnancies.
  
  
  METHODS
  This is a retrospective, cohort study of patients with a prior GBS genital colonization in pregnancy and a subsequent pregnancy with a recorded GBS culture result, from January 2000 through June 2007. Documentation of GBS status was through GBS culture performed between 35 to 37 weeks gestation. Exclusion criteria included pregnancies with unknown GBS status, patients with GBS bacteriuria, women with a previous neonate with GBS disease and GBS finding prior to 35 weeks. Data was analyzed using SPSS 15.0. The sample proportion of subjects with GBS genital colonization and its confidence interval were computed to estimate the incidence rate. Logistic regression was performed to assess potential determinants of GBS colonization. Regression coefficients, odds ratios and associated confidence intervals, and p-values were reported, with significant results reported.
  
  
  RESULTS
  There were 371 pregnancies that met the test criteria. There were 151 subsequent pregnancies with GBS genital colonization and 220 without GBS recolonization. The incidence of GBS recolonization on patients with prior GBS genital colonization was 40.7% (95% confidence interval 35.7-45.69%). The incidence rate for the sample was significantly larger than 30% (p < .001), which is the estimated incidence rate for all pregnant women who are GBS carriers regardless of prior history.
  
  
  CONCLUSIONS
  These results suggest that patients with a history of GBS are at a significantly higher risk of GBS recolonization in subsequent pregnancies.
authors.affiliation: Department of Obstetrics and Gynecology, Resurrection Health Care/Saint Joseph Hospital, Chicago, IL 60657, USA. maria.tam@reshealthcare.org
authors.forename: Teresa
authors.initials: T
authors.lastname: Tam
authors.forename: Ewa
authors.initials: E
authors.lastname: Bilinski
authors.forename: Emily
authors.initials: E
authors.lastname: Lombard
mesh_terms: D000293:Adolescent; D000328:Adult; D002641:Chicago / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D016017:Odds Ratio; D010502:Perineum / Q000382:microbiology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D013292:Streptococcus agalactiae / Q000302:isolation & purification*; D014621:Vagina / Q000382:microbiology*; D055815:Young Adult