A new carbapenem antibiotic and renal dipeptidase inhibitor, imipenem/cilastatin sodium (MK-0787/MK-0791) were studied for the distribution into various tissues and for clinical aspects in obstetrical and gynecological fields. The following results were obtained. Concentrations of the drug in arterial blood, venous blood, and internal genital organs following an intravenous drip infusion were measured. The results demonstrated good transfer of the drug into various internal genital organs. Four patients with bacterial infections were treated with MK-0787/MK-0791. Therapeutic results were good in 2 cases for, an effective rate of 50%. No side effects were noted in any cases. The above results suggested that MK-0787/MK-0791 may be a useful antibiotic for infectious diseases in the field of obstetrics and gynecology.