ABSTRACT: Clindamycin is widely used in a variety of obstetric and gynecologic infections. Despite in vitro and clinical evidence of activity against anaerobes, genital organ tissue levels resulting from intravenous administration of the drug have not previously been reported. Following a single intravenous infusion of 600 mg of clindamycin phosphate, tissue levels were determined in operative specimens obtained from ten women. Specimens of cervix, uterus, fallopian tube, and ovary were obtained, and mean Clindamycin levels for each site were: cervix, 2,63 μg/ml; endometrium, 5.58 μg/ml; myometrium, 2.39 μg/ml; fallopian tube, 2.96 μg/ml; and ovary, 3.74 μg/ml. The mean serum level was 6.26 μg/ml at the time of uterine artery interruption. The clindamycin concentrations at all sites exceeded the usual therapeutic minimal inhibitory concentration, substantiating the usefulness of clindamycin in obstetric and gynecologic anaerobic infections.