vasectomy

Male sterilization; an operation to cut and tie the ducts (see vas deferens) that carry sperm from the testes to the penis. Vasectomy does not affect sexual performance, but the semen produced at ejaculation no longer contains sperm.

Some surgical attempts to reopen the duct have been successful, and some have opened spontaneously, thus making conception possible. Initially there were concerns of lower life expectancy due to increased risks of testicular or prostate cancer. However, a large-scale study in Boston in 1992 found that an increased rate of lung cancer was offset by a reduced rate of cardiovascular disease.