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

Abstract

Background: 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. Case presentation: 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. Conclusion: 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.

Post-Vasectomy Semen Analysis: Optimizing Laboratory Procedures and Test Interpretation through a Clinical Audit and Global Survey of Practices

“…On the other hand, recanalization is considered when motile sperm or rising sperm concentrations are seen after achieving azoospermia or RNMS [ 7 ]. Pregnancy due to recanalization may result from early or late failure, which occurs in 1 in 250 patients and 1 in 2,000 patients, respectively [ 7 25 ].…”

“…In a study conducted by Jamieson et al (2004) [ 26 ], the cumulative probability of failure per 1,000 procedures (95% confidence interval) was 7.4 (0.2–14.6) 1 year post vasectomy and 11.3 (2.3–20.3) at 2, 3, and 5 years. In a case report, a pregnancy was reported 7 years after vasectomy and this was attributed to late recanalization [ 25 ]. In another study, paternity was reported despite negative semen analysis reports and the births occurred 1 to 5 years after vasectomy [ 27 ].…”

“…Alderman [ 28 29 ], who used ligation and excision for vas occlusion, reported four pregnancies among 5,331 men who completed the recommended PVSA regimen, giving a rate of about 1 in 1,300. A few cases confirmed paternity based on genetic testing even though the men had had PVSA previously showing azoospermia [ 25 27 30 31 ]. The true incidence of late recanalization is difficult to estimate, as PVSA is rarely repeated after a test showing azoospermia or RNMS [ 7 15 ].…”

“…Spermatozoa may reappear in the ejaculate as a result of spontaneous recanalization and do not depend on the surgical procedure [ 30 31 ]. Therefore for the physicians, counseling is prudent to ensure that the patient and the partner fully understand the implications of non-compliance and the possibility of recanalization and pregnancy ( Table 4 ) [ 25 27 32 33 34 35 36 37 38 39 ]. This was strongly reflected in the survey with 90.3% counseling their patients about the risk of recanalization and 82% highly recommending the need for a vasectomy consent form based on expert consensus.…”