How Reliable Is a Vasectomy?

Tubal ligation and vasectomy represent two methods of sterilization pursued by women and men, respectively. Since vasectomy is the simpler, safer, and less costly of the two, many couples choose it over tubal ligation for their method of birth control. Both exhibit the same rate of reliability. Although the likelihood of pregnancy following a vasectomy is small, the possibility still exists.

Procedure

• A vasectomy involves cutting the tubes, or vasa deferentia, that allow the sperm from the testis to enter the semen. Prior to 1988, small incisions made using scalpels permitted access to the tubes. Introduction of the no-scalpel technique in 1988 simplified the procedure further by eliminating the need for incisions and stitches.

Reliability

• According to a survey conducted and published by Family Health International, pregnancy resulted in one of every 1000 vasectomies performed. In cases where high adherence to post-surgery birth control precautions were followed as directed, pregnancy resulted in one of every 2000 vasectomies performed.

Reasons for Failure

• Vasectomies fail most often when couples fail to use an additional form of birth control during the initial months following the procedure. Sperm can remain in a man's reproductive system for months after a vasectomy. Until lab results confirm absence of sperm in the semen, the possibility of pregnancy exists. Approximately one pregnancy for every 4000 vasectomies occurs because the vasa deferentia reconnect.