OBJECTIVE: To study the semen analysis values required to cause a pregnancy after vasectomy reversal (VR). Vasectomy reversal is increasingly performed on men who wish to regain fertility after elective sterilization. Despite a thorough understanding of predictors of vasal patency after surgery, little is known about the patients' semen parameters and pregnancy potential. DESIGN: Retrospective case-control study. SETTING: Tertiary-care hospital. PATIENT(S): A total of 139 patients who underwent VR at the Cleveland Clinic from 2010 to 2014. INTERVENTION(S): Vasectomy reversal. MAIN OUTCOME MEASURE(S): Pregnancy, semen parameters. Data regarding patient and spouse ages, obstructive interval, intraoperative findings, procedure performed, postoperative semen results, and spontaneous pregnancy outcome were collected. Pearson and t tests were used to analyze categoric and numeric data, respectively. Average semen reference values were developed. RESULT(S): The mean obstructive interval was 9.5 ± 1.2 years. Spontaneous pregnancy was achieved by 49.6% of patients (69/139) and was directly related to better intraoperative vasal fluid quality and postoperative sperm concentration, motility, and strict morphology. The reference ranges of postoperative semen parameters of patients with spontaneous pregnancy were substantially lower than normal values published by the World Health Organization (WHO) in 2010. Spontaneous pregnancy was reported in 15%, 21.3%, and 14.8% of patients with a sperm concentration of <5 million/mL, a sperm motility of <10%, and a normal morphology of <1%, respectively. CONCLUSION(S): Normal ranges of semen parameters as established by the 2010 WHO standards may not adequately predict post-vasectomy reversal fertility. Significantly lower post-reversal semen parameters may be considered to be sufficient in previously fertile patients after reversal compared with the normal population.
