In order to assess clinical utility of cefminox (CMNX, MT-141), its transference into internal genital organ tissues and pelvic dead space was determined. In addition, transference of CMNX from maternal blood into fetal umbilical cord blood as well as into amniotic fluid was evaluated. In the clinical study, CMNX was administered in 4 cases. The following results were obtained. Transference into internal genital organ tissues; The concentration ratio of each tissue against serum concentration ranged from 25.3 to 42.7%, showing favourable transference as compared to other cephems. Transference into pelvic dead space; At 6 hours after intravenous injection of 1 g CMNX, its concentration in the pelvic dead space reached its peak of 38.8 micrograms/ml of the serum concentration, followed by gradual decrease. Transference into umbilical cord blood and amniotic fluid; Following intravenous injection of 1 g CMNX, its concentration in umbilical cord blood became almost similar to that of maternal blood at about 3 hours later, being 20 micrograms/ml. After that, it tended to decrease in accordance with the concentration in maternal blood. It appears that the drug persists for a more prolonged period in amniotic fluid. RESULTS Clinically, CMNX was used in the treatment of 4 cases including 2 cases of lymphocystitis, 1 case of intrapelvic cellulitis and 1 case of postoperative wound abscess, and the results obtained were rated as excellent in 1 case, good in 2 cases and poor in 1 case with an efficacy rate of 75%. None of the cases treated experienced adverse reactions nor any laboratory abnormalities were observed.