title: Group B Streptococcus colonization during pregnancy and maternal-fetal transmission in Zimbabwe.
abstract: OBJECTIVE
  To explore risk factors for group B Streptococcus (GBS) colonization during pregnancy and at delivery, estimate the predictive value of early GBS colonization for colonization at delivery and in the newborn, and explore the relationship to adverse perinatal factors.
  
  
  METHODS
  Cohort study of pregnant women from three communities in Zimbabwe.
  
  
  METHODS
  Information collected by questionnaire at inclusion and from delivery records. Vaginal and rectal swabs collected for GBS culture at 20 and 26 weeks gestation, at delivery and from the newborn infant.
  
  
  METHODS
  GBS colonization in pregnancy, colonization of mother and newborn, and perinatal factors.
  
  
  RESULTS
  GBS culture results were obtained at one or more occasion for 780 (75.2%) of 1,037 women recruited. Altogether, 470/780 women (60.3%) tested positive for GBS, with colonization rates at 20, 26 weeks and delivery of 47%, 24.2% and 21%, respectively. Positive GBS culture at 20 and 26 weeks gestation had a low positive predictive value on colonization at delivery and in the newborn. Women living in rural areas were significantly more often colonized than those who lived in urban areas (p < 0.001). Other socio-economic, demographic and obstetric factors were not statistically associated with GBS colonization. GBS transmission was not statistically significantly associated with adverse perinatal outcomes.
  
  
  CONCLUSIONS
  GBS colonization was common among pregnant women in Zimbabwe. Dwelling in a rural area was significantly associated with GBS colonization while other risk factors were not. Early GBS colonization had a low predictive value for colonization at delivery and colonization was not associated with adverse perinatal outcome.
authors.affiliation: Department of Medical Microbiology, University of Zimbabwe College of Health Sciences (UZ), Harare, Zimbabwe.
authors.forename: Rooyen T
authors.initials: RT
authors.lastname: Mavenyengwa
authors.forename: Jan Egil
authors.initials: JE
authors.lastname: Afset
authors.forename: Berit
authors.initials: B
authors.lastname: Schei
authors.forename: Synnøve
authors.initials: S
authors.lastname: Berg
authors.forename: Tone
authors.initials: T
authors.lastname: Caspersen
authors.forename: Håkon
authors.initials: H
authors.lastname: Bergseng
authors.forename: Sylvester R
authors.initials: SR
authors.lastname: Moyo
mesh_terms: D001724:Birth Weight; D015331:Cohort Studies; D036861:Delivery, Obstetric; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D008470:Meconium; D011237:Predictive Value of Tests; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology / Q000382:microbiology*; D012307:Risk Factors; D012424:Rural Population; D013290:Streptococcal Infections / Q000453:epidemiology / Q000635:transmission*; D013292:Streptococcus agalactiae; D014505:Urban Population; D015030:Zimbabwe / Q000453:epidemiology