Group B Streptococcus (GBS) remains a leading cause of invasive disease in neonates and certain adult populations including pregnant women. The development of GBS disease is initiated by the asymptomatic colonization of the female genital tract and during pregnancy can be associated with chorioamnionitis, puerperal endometritis and preterm labor. Approximately 20-30% of healthy women are colonized rectovaginally with GBS; the majority of infants born to these women will themselves become colonized with the bacterium.  Newborn infection results from ascending infection of the bacterium through the placental membranes to initiate infection in utero, or results during the birthing process.  Current guidelines focus on a single strategy of universal screening for GBS vaginal carriage during pregnancy with intrapartum antibiotic prophylaxis for all women who are carriers. However, these strategies have not prevented GBS neonatal sepsis and meningitis and there is increased concern of emerging patterns of antibiotic resistance in GBS and other organisms present during treatment.