1. Home>
2. Specialties>
3. Pediatrics and Adolescent Medicine>
4. Summary and Comment

Universal Screening for Group B Strep: Success with Room for Improvement

Missed opportunities for prevention include women who deliver preterm and women with unknown or false-negative screening results.

In 2002, national guidelines called for universal screening for group B streptococcus (GBS) in pregnant women at 35–37 weeks’ gestation. In a multisite, retrospective, population-based study, investigators assessed implementation of the guidelines, missed opportunities for prevention, and the current burden of disease to identify further preventive measures.

In a 10-state surveillance network involving 819,528 births in 2003 and 2004, the authors identified all 254 infants with early-onset (<7 days of age) GBS disease and a random sample of 7437 noninfected newborns; 89% of all infants and 74% of infants with GBS disease were delivered at term. Data were compared with those from a similar surveillance survey in 1998–1999. The rate of GBS screening before delivery increased from 48% in 1998–1999 to 85% in 2003–2004. Only 49% of women in the study cohort had been screened at 35–37 weeks’ gestation (36% had unknown screening dates). Among screened women, 98% had documented screening results, and 24% of these were positive for GBS. The percentage of mothers who received intrapartum antibiotics increased from 27% in 1998–1999 to 32% in 2003–2004.

Mothers who delivered preterm were significantly less likely to be screened and to receive chemoprophylaxis when indicated than mothers who delivered at term. Women with GBS who had short intervals (<4 hours) between admission and delivery were less likely to receive intrapartum antibiotics than women with longer admission-to-delivery intervals. Preterm infants had a higher incidence of GBS disease than term infants (0.72 vs. 0.26 cases per 1000 live births). However, 74% of early-onset GBS cases were in term infants, and 61% of these infants were born to mothers who had tested negative for GBS. The authors conclude that the recommendation for universal GBS screening was adopted quickly, but missed opportunities for prevention still exist in women who deliver preterm and in women with unknown or false-negative screening results.

Comment: If you practiced medicine in the 1970s when neonatal infection with GBS was rampant, the successes of screening for and treating this infection during pregnancy will seem truly remarkable. Despite development of polymerase chain reaction–based tests for GBS that can be performed in intrapartum patients and provide results in less than 1 hour, the clinical utility of such rapid testing remains uncertain. For now, we need to close the gaps, promote antenatal screening, and develop systems to ensure appropriate antibiotic treatment when indicated. Future availability of a group B streptococcal vaccine could provide substantial additional benefit.

— William P. Kanto, Jr., MD

Published in Journal Watch Pediatrics and Adolescent Medicine June 17, 2009

Citation(s):

Van Dyke MK et al. Evaluation of universal antenatal screening for group B streptococcus. N Engl J Med 2009 Jun 18; 360:2626.

• Original article (Subscription may be required)
• Medline abstract (Free)

Reader Remarks:

Read all Reader Remarks on this article

• Universal Screening for Group B Strep: Success with Room for Improvement
  AP Oppenheimer, 19 Jun 2009 1:55 PM EST
  Improvement has been remarkable so far, but to make it jump higher, policy decisions need to be made. The situation... [more]