We report the results of a screening study on pregnant women and early onset neonatal group B streptococcal infections in Sofia, Bulgaria, July 2009-July 2010. Women were studied for risk factors at delivery, intrapartum antibiotic prophylaxis (lAP) and outcome for the newborns. All GBS positive women who had risk factors at delivery gave birth to newborns with neonatal infection despite the IAP given in 50% of the cases. The majority of the GBS positive women who had no risk factors at delivery gave birth to healthy newborns although only 32% of them received IAP However 11% of the GBS positive women without risk factors delivered children with neonatal infection. We consider that IAP should be given to all GBS positive women to prevent from neonatal infection. The dominant GBS serotypes were ll, 11 and la. The isolates were 100% susceptible to penicillin, cefazolin, cefotaxime, vancomycin and 91.66% susceptible to erythromycin and clindamycin, the resistant strains being from the MLSB phenotype.