To examine patient compliance, complications, and significance of rare nonmotile sperm (RNMS) after no-scalpel vasectomy.

We reviewed the records of 690 consecutive men who had undergone vasectomy at our institution between 1996 and 2002. All men were instructed to submit two initial semen samples for analysis (3 and 4 months after vasectomy) and additional samples (at 2-month intervals) if sperm were identified on the initial and subsequent analyses. All patient complaints (telephone and clinic visit) were recorded.

A total of 315 men (45.6%) did not submit any semen samples. Of the 295 men who submitted two samples, 176 (60%) were azoospermic, 110 (37%) had RNMS, and 9 men (3%) had rare motile sperm (the vasectomy of 1 of these 9 men subsequently failed). Of the 110 men with RNMS, 83 submitted one or more additional semen samples. Of these 83 men, 62 (75%) had become azoospermic, 20 (24%) had persistent RNMS, and 1 (1%) subsequently had a failed vasectomy (with motile sperm). The 2 patients with failure underwent a repeat vasectomy (failure rate 0.67% [2 of 295]). A total of 69 patients (10%) reported a complaint, but only 9 (1.5%) of these men returned for clinical examination. No surgical complications and no pregnancies occurred.

Our data show that despite aggressive counseling, compliance with follow-up testing is very poor. Patient-reported complaints are common but minor. We found that most men with RNMS become azoospermic and propose that the presence of RNMS is consistent with a successful vasectomy. However, long-term, prospective studies are needed to assess the risk of late failure in men with RNMS.