High percentage of abnormal semen parameters in a prevasectomy population.

OBJECTIVE

To evaluate semen characteristics, testicular volume, and hormonal levels of normal fertile men requiring vasectomy for sterilization.

DESIGN

Retrospective study.

SETTING(S): Academic medical centers.

PATIENT(S): A total of 889 patients underwent a vasectomy for sterilization.

INTERVENTION(S): None.

MAIN OUTCOME MEASURE(S): Semen volume, sperm concentration, motility, and morphology according to the World Health Organization (WHO); complex motion parameters evaluated by computer-assisted semen analyzer; FSH, LH, and T levels; and both testicular volumes.

RESULT(S): When compared with the WHO values, 87.2% of the patients presented normal sperm morphology below the normal level. The other semen parameters (semen volume, pH, sperm concentration, and sperm motility) differed from the WHO parameters in 6%-32.2% of patients. Semen volume and sperm concentration presented a progressive increase according to the duration of sexual abstinence. However, patients with 5 days or more of abstinence had a decrease in sperm motility. Mean testicular size had the strongest correlation with serum FSH levels, total sperm count, and sperm concentration.

CONCLUSION(S): Low sperm motility and morphology were found in men who request a vasectomy for sterilization. Semen volume and sperm concentration present a progressive increase and sperm motility a decrease according to the duration of sexual abstinence. Sperm concentration had stronger correlations with testicular size than did sperm quality. Therefore, the WHO normal values need to be reconsidered.