A vasectomy reversal operation involves the rejoining of the vas deferens, the tube which carries sperm from the testes to the penis, and which will have been cut in the original vasectomy operation. This operation is known as a vasovasostomy. In more difficult cases, a vasoepididymostomy may be carried out, where the vas deferens is connected to the epididymis.
The success rate for pregnancy after vasectomy reversal depends to some extent on how long it has been since the vasectomy has been performed. Under three years, a pregnancy rate of 76% has been recorded in a clinical study. Over fifteen years, this fell to 30%.