To study the transfer of cefuzonam (CZON, L-105) into female genital organs, concentrations of the compound in pelvic dead space exudate were measured in cases of radical hysterectomy due to cervical cancer and analyzed by the two-compartment model. When CZON 1 g was drip-infused intravenously, the concentration in the cubital vein blood was 46.95 micrograms/ml at 1 hour after the start of infusion. Concentrations in the pelvic dead space exudate reached the peak of 11.29 micrograms/ml at 2.44 hours after the start, were higher than 4 micrograms/ml after 8 hours and were higher than 1.7 micrograms/ml after 12 hours. The area under the concentration-time curve in the pelvic dead space exudate was 77.85 micrograms X hr/ml. From these results CZON was considered to be effective when administered at 1 g against infections of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, and haemophilus influenzae, but increased dose levels seemed necessary against infections of Staphylococcus epidermidis and Bacteroides fragilis. In 3 cases of obstetric and gynecological infections the efficacy of CZON was good in 2 cases and unknown in the other case.