The duration of infertility: an important datum for the fertility prognosis of men with semen abnormalities.

In a group of 584 men with semen abnormalities the relationship between conception and the duration of infertility was studied. "Spontaneous" pregnancies were reported significantly more frequently for men with an infertility duration of less than 2 years than for men with an infertility duration of more than 2 years. Seventy-three conceptions occurred "spontaneously" and sixty-six occurred while the men were undergoing different forms of therapy. When all pregnancies were considered together it appeared that the "chance" of fathering a child after 2 years of infertility was still about 20% during the ensuing 3 years.