As with all surgery, there is the possibility of complications, even with a minor operation like a vasectomy. Complications that may occur soon after your vasectomy include the following:
Internal bleeding in the scrotum may cause increasing pain, great swelling, or an enlarging mass. If you have these symptoms, which usually occur within two days after surgery, please call your doctor.
Infection in the incision very rarely occurs a short time after surgery. Be sure to call your doctor if you suspect an infection.
Other complications, though also rare, can arise in the first few months after surgery.
Sperm granuloma, which occurs in about 3% of all vasectomies, is a lump at the site where the vas deferens is tied off and is caused by a leakage of sperm. The lump usually dissolves by itself. Occasionally, surgery may be required to remove it.
Congestion caused by sperm left in the epididymis may cause some aching about 3-12 weeks after surgery. The congestion usually disappears without the need for treatment.
Sperm antibodies are a common response of the body to proteins formed from the absorbed sperm. These antibodies have not been found to be harmful in humans. Between 50 – 70% of men develop sperm antibodies after a vasectomy.
Spontaneous formation of a new vas deferens
Spontaneous formation of a new vas deferens, or recanalization through the scar tissue left by the vasectomy very rarely occurs. This can usually be detected by a semen test after surgery. Recanalization occurs in 1 out of 2,000 men after a negative semen test has been performed at 8 weeks or longer after surgery. The failure rate after vasectomy is 1 in 250-400 if you fail to do a sperm test follow-up.