In 14 patients by bilateral retroperitoneal lymph node dissection for nonseminoma tumors of the testes, several sexual functions before and after node dissection were compared. All patients had normal sexual function before the operation. After the operation, antegrade ejaculation was found to have disappeared completely in 12 patients, retrograde ejaculation was demonstrable in ten of these patients. In ten patients, antegrade ejaculation was restored after treatment with 25 mg imipramine twice daily by mouth. In the two patients who still showed antegrade ejaculation, albeit diminished, imipramine medication led to an increased number of spermatoza. During imipramine medication, the partners of five patients became pregnant. The preliminary conclusion from these findings is that ejaculation disorders, which most males develop after bilateral retroperitoneal lymph node dissection, can be successfully treated with daily oral doses of 25-50 mg imipramine in the majority of patients who still desire children.