Paternity seven years after a negative post-vasectomy semen analysis: a case report

Vasectomy is one of the permanent methods of contraception; however, the risk of conception still exists. Early failure, defined as a postoperative semen analysis showing persistent motile sperm, occurs in 1 in every 250 patients. Late failure, defined as the rejoining of the severed ends of the vas deferens, occurs in 1 in every 2000 patients.

A healthy 37-year-old British male presented to our clinic because his wife had conceived seven years after he had undergone a vasectomy. The result of his semen analysis after the vasectomy was negative, and the histopathological report confirmed that the sample contained tissue from both the left and right vas deferens. His wife conceived seven years after the procedure, and semen analysis at that time confirmed a total of 0.5 million sperm per milliliter of semen in a total semen sample of 6.3 ml. The total number of motile sperm recorded was 2.5 million.

This case shows that late recanalization can occur up to seven years after a vasectomy. Patients should be informed prior to the procedure that late recanalization, although rare, may still occur. Post-vasectomy paternity necessitates further counseling to ensure that the patient and the patient's partner fully understand the implications and options available to them.