RESUMEN
The aims of this prospective, non-comparative study were to determine time to azoospermia and vasectomy success rate based on the results of semen analysis. A total of 334 men seeking vasectomy at a clinic in Urmia city, Islamic Republic of Iran were followed bi-weekly up to 24 weeks after vasectomy or until azoospermia was confirmed via semen analysis. The cumulative life table rate for azoospermia was 93/100 men [95% Cl: 88.1 to 97.9]. The median time to azoospermia was 10 weeks. By week 24 of follow-up, 3.3% of participants had failed to achieve azoospermia. One pregnancy was reported during the study period and attributed to user failure. The results suggest that men can begin to rely on vasectomy for contraception 12 weeks after no-scalpel vasectomy using fascial interposition performed by an experienced surgeon