title: Assessment of intrapartum antibiotic prophylaxis for the prevention of early-onset group B Streptococcal disease.
abstract: BACKGROUND
  Most early-onset group B streptococcal (GBS) disease in recent years has occurred in newborns of prenatally GBS-negative mothers who missed intrapartum antibiotic prophylaxis (IAP). We aimed to assess the accuracy of prenatal culture in predicting GBS carriage during labor, the IAP use, and occurrence of early-onset GBS disease.
  
  
  METHODS
  We obtained vaginal-rectal swabs at labor for GBS culture from 5497 women of ≥ 32 weeks' gestation and surface cultures at birth from newborns between February 5, 2008 and February 4, 2009 at 3 hospitals in Houston, TX and Oakland, CA. Prenatal cultures were performed by a healthcare provider during routine care, and culture results were obtained from medical records. The accuracy of prenatal culture in predicting intrapartum GBS carriage was assessed by positive and negative predictive values. Mother-to-newborn transmission of GBS was assessed. Newborns were monitored for early-onset GBS disease.
  
  
  RESULTS
  GBS carriage was 24.5% by prenatal and 18.8% by labor cultures. Comparing prenatal with labor GBS cultures of 4696 women, the positive predictive value was 50.5% and negative predictive value was 91.7%. IAP, administered to 93.3% of prenatally GBS-positive women, was 83.7% effective in preventing newborn's GBS colonization. Mother-to-newborn transmission of GBS occurred in 2.6% of elective cesarean deliveries. Two newborns developed early-onset GBS disease (0.36/1000 births); the prenatal GBS culture of one was negative, the other's was unknown.
  
  
  CONCLUSIONS
  IAP was effective in interrupting mother-to-newborn transmission of GBS. However, approximately 10% of prenatally GBS-negative women were positive during labor and missed IAP, whereas approximately 50% of prenatally GBS-positive women were negative during labor and received IAP. These findings emphasize the need for rapid diagnostics during labor.
authors.affiliation: Division of Intramural Research and Division of Epidemiology, Statistic, and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA. Link@mail.nih.gov
authors.forename: Feng-Ying C
authors.initials: FY
authors.lastname: Lin
authors.forename: Leonard E
authors.initials: LE
authors.lastname: Weisman
authors.forename: Parvin
authors.initials: P
authors.lastname: Azimi
authors.forename: Amy E
authors.initials: AE
authors.lastname: Young
authors.forename: Kathleen
authors.initials: K
authors.lastname: Chang
authors.forename: Mikhaela
authors.initials: M
authors.lastname: Cielo
authors.forename: Patricia
authors.initials: P
authors.lastname: Moyer
authors.forename: James F
authors.initials: JF
authors.lastname: Troendle
authors.forename: Rachel
authors.initials: R
authors.lastname: Schneerson
authors.forename: John B
authors.initials: JB
authors.lastname: Robbins
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D019072:Antibiotic Prophylaxis; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D008875:Middle Aged; D018743:Perinatal Care; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology / Q000517:prevention & control; D013290:Streptococcal Infections / Q000382:microbiology / Q000517:prevention & control* / Q000635:transmission; D013292:Streptococcus agalactiae / Q000302:isolation & purification; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents