Although antepartum screening for Group B Streptococcus is not ideal, it may be the most practical approach until rapid tests are proven to be useful in this clinical setting. The efficacy has been established for intrapartum chemoprophylaxis with a penicillin antibiotic of patients with a positive antepartum culture. There is evidence that supports the concept for selective intrapartum chemoprophylaxis in some populations. Intrapartum chemoprophylaxis prevents maternal morbidity. Rapid tests for intrapartum diagnosis of Group B streptococcus colonization appear promising, providing results are available in time for therapy to be administered before delivery.