Abstract: A method and instrumentation for sterilization of females has been devised in which one or more hypodermic needles can be inserted into the uterus to a predetermined position or location at the uterine cornu and the internal tubal ostra followed by injecting a sclerosing agent which produces a chronic lesion at that point. The entire needle assembly is characterized by slidable mounting of the needle or needles within a guide or sleeve projecting forwardly from a disposable cartridge, and a hand-held actuator is provided to selectively control successive advancement of each needle through the needle guide into the tissue and advancment of the ampule or cartridge to force the sclerosing agent or other medicament through the needle. Thereafter, the needle assembly may either be withdrawn or relocated to another position for injection of medicament through the same or other needle advancing through the same needle guide into the opposite cornul portion.