Transrectal ultrasonography in the evaluation of the infertile man: a report of 3 cases. The traditional evaluation of the infertile man with azoospermia or low ejaculate volume includes determination of serum testosterone and follicle-stimulating hormone levels, a seminal fructose test, post-ejaculate urinalysis and, sometimes, vasography. Transrectal ultrasonography, a technique currently familiar to most urologists, recently has been added to our diagnostic armamentarium. This office-based imaging procedure provides an accurate assessment of the prostate, ejaculatory ducts and seminal vesicles, which can be helpful in the evaluation of certain infertile patients. We describe 3 patients who presented with either azoospermia or decreased ejaculate volume in whom transrectal ultrasonography had a critical role in the fertility evaluation. The clinical indications for and interpretation of transrectal ultrasonography in the infertile population are described. Transrectal ultrasonography currently is the most accurate, inexpensive and readily available noninvasive imaging technique used to diagnose obstruction of the ejaculatory ducts in the infertile patient with either azoospermia or low ejaculate volume. 