Clinical significance of unilateral testicular obstruction in subfertile males

Unilateral testicular obstruction has been defined by exploratory scrototomy in 80 spontaneously infertile males. The most common sites of obstruction were either in the tail of the epididymis after previous infection (40 cases) or in the vas deferens due to congenital absence or after previous infection or surgery (24 cases). Half of the patients had severe oligozoospermia (less than 5 million/ml) and three-quarters had developed antisperm antibodies, often in high titres. Spermatogenesis was shown by testicular biopsy to be normal (Johnsen score-count greater than 8.0) in almost all of the obstructed testes, and serum FSH levels were normal. Following surgical reconstruction, with prednisolone therapy if indicated by high antisperm antibody titres, 19 (32%) of 60 patients with adequate follow-up successfully impregnated their female partners, with the best results occurring in 30 men who started with sperm counts less than 5 million/ml, 12 of whom (40%) were successful. Removal of irreparably blocked testes in 10 men led to profound falls in high antisperm antibody titres, with production of two pregnancies. Unilateral testicular obstruction appears to be a correctable cause of infertility in some human males.