Group B Streptococcus (GBS) In Pregnancy

OVERVIEW

Group B Streptococcus (GBS) most commonly refers to Streptococcus agalactiae. It is the most common neonatal infection and is an important consideration during pregnancy.

WHY DO WE CARE ABOUT GBS DURING PREGNANCY?

Infection of the neonate can lead to medical complications.

WHEN DO WE SCREEN FOR GBS IN PREGNANCY? 

Screening practices may vary depending upon the clinical context. It is important to keep in mind that GBS screening is most accurate if performed 3-5 weeks before the estimated delivery date.

Universal screening (patients with no signs of preterm labor) occurs at 35-37 weeks gestation (estimated delivery of 40-42 weeks).

HOW DO WE SCREEN FOR GBS?

Culture of both the vagina and rectum is the most sensitive screening method for detecting GBS.

WHAT DO WE DO IF WE SUSPECT GBS WILL COMPLICATED THE PREGNANCY?

Penicillin prophylaxis is given 4 hours before delivery to prevent transmission of GBS to the fetus/neonate

WAHT ARE INDICATIONS FOR GIVING ANTIBIOTIC PROPHYLAXIS?

The following situations are all indications for giving patients penicillin prophylaxis is indicated 

  • Prior delivery complicated by neonate GBS infection
  • GBS bacteriuria or GBS urinary tract infection during the course of the current pregnancy (regardless of treatment received for these issues)
  • GBS positive rectovaginal culture 3-5 weeks prior to delivery
  • Unknown GBS status (no culture at least 5 weeks before delivery) PLUS the presence of any of the following
    • < 37 weeks gestation
    • Intrapartum fever
    • Rupture of amniotic membranes for ≥ 18 hours

 

Page Updated: 10.08.2016