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Introduction ⬇

Group B Streptococcus (GBS) is a frequent cause of newborn pneumonia. Sepsis and meningitis are also common problems of GBS infection. Preterm infants are more susceptible to GBS disease, but it occurs most often in full-term infants.

The ACOG guidelines recommend that all pregnant women should be screened for anogenital group B streptococcal colonization at 36–37 weeks’ gestation.

Procedure ⬆ ⬇

  1. Swab the distal vagina and anorectum using one or two swabs. See Chapter 7 for more information. Label with the patient’s name, date and time of collection, and test ordered. Place swabs in transport medium and send to laboratory.

  2. Report results on prenatal record and ensure that a copy is available at the hospital where delivery of the infant is anticipated.

Clinical Implications ⬆ ⬇

  1. A positive culture indicates a GBS carrier, and results should be recorded on the prenatal record so that it is available to the healthcare providers at the time and place of delivery.

  2. Intrapartum antibiotic prophylaxis should be considered with positive culture results by weighing the risks and benefits of treatment with each GBS carrier who is pregnant.

  3. Prophylaxis should be continued throughout active labor until delivery.

  4. Women with GBS isolated from the urine at any time during the current pregnancy, or who had a previous infant with invasive GBS disease, should receive intrapartum antibiotic prophylaxis and do not need third-trimester screening for GBS colonization (AII). Women with GBS urinary tract infection with or without symptoms detected during pregnancy should be treated according to current standards of care for urinary tract infection during pregnancy and should receive intrapartum antibiotic prophylaxis to prevent early-onset GBS disease (AIII).

  5. If GBS status is unknown at the onset of labor, intrapartum chemoprophylaxis should be given to women with the following risk factors:

    1. <37 weeks’ gestation

    2. Ruptured membranes ≥18 hours

    3. Temperature ≥100.4 °F (>38 °C)

Interventions ⬆ ⬇

Pretest Patient Care

  1. Explain the screening test to the patient, including the risks of GBS disease to newborn.

  2. Follow guidelines in Chapter 1 for safe, effective, informed pretest care.

Posttest Patient Care

  1. Review test results; report and record findings. Modify the nursing care plan as needed.

  2. Monitor the patient and counsel appropriately.

  3. Oral antibiotics should not be used to treat pregnant women with a positive anogenital GBS culture because they are not effective in eliminating the carrier status or preventing neonatal disease. Treatment should take place intrapartum.

  4. If GBS bacteria with or without symptoms are detected in pregnancy, treatment should be considered at the time of diagnosis because this usually indicates a heavily colonized individual. Intrapartum treatment is also indicated for this individual.

  5. If GBS status is unknown at the onset of labor (culture not done, incomplete, or results unknown) and any of the following are present—delivery will be at <37 weeks of gestation, amniotic membrane rupture ≥18 hours, intrapartum temperature ≥100.4 °F (≥38.0 °C), or intrapartum rapid test is positive for GBS—then GBS prophylaxis is indicated (ACOG Committee Opinion No. 485: Prevention of early-onset group B streptococcal disease in newborns).

  6. Follow guidelines in Chapter 1 for safe, effective, informed posttest care.

Reference Values ⬆

Normal