Algorithm for preventing early onset group B streptococcal infection in newborns, with inclusion of perinatal screening of mothers at 35-37 weeks of gestation (see Figure 1):
(1) Administer prophylactic antibiotics if
(1a) the patient does have history of a previous infant with invasive group B streptococcal infection
(1b) the patient has had group B streptococcal bacteriuria during this pregnancy
(1c) cultures of rectum and vagina taken at 35-37 weeks gestation are positive for group B streptococcus
(1d) culture data is not available and delivery is at less than 37 weeks of gestation
(1e) culture data is not available and the mother has an intrapartum temperature of >= 100.4 °F (>= 38 °C)
(1f) culture data is not available and the membranes have been ruptured for 18 hours or more
(2) Do not administer prophylactic antibiotics if:
(2a) the patient does not have history of a previous infant with invasive group B streptococcal infection
(2b) the patient has not had group B streptococcal bacteriuria during this pregnancy
(2c) cultures of rectum and vagina taken at 35-37 weeks gestation are negative for group B streptococcus
(2d) culture data is not available and the mother does not have an intrapartum temperature of >= 100.4 °F (>= 38 °C)
(2e) culture data is not available and the membranes are not ruptured for more than 18 hours
Regimens recommended for prophylaxis to prevent perinatal group B streptococcal infection:
(1) patients not penicillin allergic
(1a) recommended: penicillin G. 5 million units are given as an intravenous loading dose, then 2.5 million units are given IV every 4 hours until delivery
(1b) alternative: ampicillin. 2 grams are given as an intravenous loading dose, followed by 1 gram IV every 4 hours until delivery
(2) patients penicillin allergic
(2a) recommended: clindamycin. 900 mg is given intravenously every 8 hours until delivery
(2b) alternative: erythromycin. 500 mg is given intravenously every 6 hours until delivery.
