|A highly effective procedure, the failure rate of vasectomy is less than 1%
As of date, vasectomy is the most effective long term contraceptive option in a man and is considered as a much safer method of family planning. The failure rates of vasectomy have been reported to be less than 1%. Simply, one could say that it is 99% effective, which is far higher than use of condoms where the effectiveness is roughly about 88%.
One important factor, which influences the failure rate, is the length of the vas deferens removed. Longer the segment removed, lesser are the chances of the cut ends joining together (called recannalisation) and failure. Removal of longer section of vas however is associated with reduced chances of successful reversal (if the patient wishes to have a child in the future).
If any sperms are found in the ejaculate, 3 months following the surgery, the procedure should be repeated.