Swabs were cultured onto selective Granada medium and incubated at 35 • C under anaerobic conditions for 18-24hrs. Characteristic orange colonies on of GBS on Granada medium were confirmed by Streptex agglutination. Antimicrobial susceptibility was tested against penicillin, erythromycin, clindamycin, vancomycin and levofloxacin by Etest using CSLI guidelines. Serotyping was performed by latex agglutination.Results: Seventy-two (25%) pregnant women were colonized with GBS. All isolates were susceptible to penicillin (MIC 90 = 0.125mg/l), however, reduced MIC values (0.25mg/l, 0.7mg/l and 1 mg/l) were observed in three isolates. Reduced susceptibility to erythromycin (17%) and clindamycin (6%) was also observed. All isolates were susceptible to vancomycin and levofloxacin. The most common serotypes were Ia (54%), III (19%), and V (17%).Conclusion: We report a high prevalence of GBS colonization amongst pregnant women. Although penicillin remains the drug of choice for treating GBS, active surveillance should be encouraged to monitor susceptibility trends in order to detect emergence of resistance. Erythromycin and clindamycin should only be used in penicillin intolerant cases after susceptibility results are available. Vancomycin or levofloxacin may be considered in a setting of high levels of macrolide resistance. Serotype Ia was found to be the commonest serotype in this study. This is consistent with local and international findings. http://dx.