Colonization with group B streptococci in pregnancy and adverse outcome. VIP Study Group

Area of Science:

• Obstetrics and Gynecology
• Neonatal Health
• Infectious Diseases

Background:

• Group B Streptococcus (GBS) is a common bacterium that can colonize the female genital tract.
• GBS colonization during pregnancy can lead to adverse pregnancy and neonatal outcomes, including preterm birth and sepsis.

Purpose of the Study:

• To investigate the association between cervicovaginal colonization with group B streptococci (GBS) and pregnancy outcomes.
• To determine the predictive value of GBS colonization at different gestational stages for neonatal sepsis.

Main Methods:

• A prospective study involving 13,646 women across seven medical centers from 1984 to 1989.
• Genital tract cultures were performed at 23–26 weeks' gestation and at delivery.
• Comparison of prematurity and neonatal sepsis rates between GBS-positive and GBS-negative women.

Main Results:

• Heavy GBS colonization was linked to a higher risk of preterm birth and low birth weight (OR=1.5).
• Antibiotic treatment in heavily colonized women reduced the risk of adverse outcomes.
• GBS colonization at delivery, but not at 23–26 weeks gestation, significantly predicted neonatal sepsis (16 vs 0.4 per 1000 live births).

Conclusions:

• Heavy GBS colonization early in pregnancy is associated with an increased risk of preterm, low-birth-weight infants.
• Cervicovaginal GBS screening at 23–26 weeks gestation is not a reliable predictor of neonatal GBS sepsis.
• GBS colonization identified at the time of delivery is a strong predictor of neonatal sepsis.