The clinical impact of British guidelines on post-vasectomy semen analysis

INTRODUCTION: Following vasectomy, azoospermia may not be achieved and rare non-motile sperm (RNMS) may persist in the semen. International guidelines vary in management of this finding. Giving ‘special clearance’ enables vasectomy to be considered a success despite the presence of RNMS. The latest 2016 British guidelines require two centrifuged semen samples with RNMS in order to give special clearance. We investigate the impact of these latest recommendations. MATERIAL AND METHODS: Retrospectively, patients who underwent vasectomy between 2014 and 2018 were assessed. The patient sample was divided into two groups, pre- and post-implementation of the new guidelines. The primary outcome measures were (i) total number of post-operative semen samples submitted, (ii) post-vasectomy semen analysis (PVSA) outcomes, and (iii) the numbers issued special clearance. RESULTS: Implementation of the updated guidelines increased detection of RNMS from 18% to 27% (p <0.01) and increased use of repeat testing. In the two year period prior to implementation, no patients required special clearance, however, once implemented, it was offered to 10 patients. Furthermore, there was a 5-fold increase in PVSA processing costs. The first post-vasectomy semen sample demonstrated azoospermia or RNMS in 97.5% of patients. CONCLUSIONS: British guidelines are more resource intensive, result in prolonged follow-up with increasing rates of special clearance. The European Association of Urology permits clearance, not special clearance, after a single non-centrifuged sample demonstrating azoospermia or RNMS. Bringing British recommendations in-line with European guidance would enable clearance in up to 97.5% of patients following a single sample at 12 weeks.