Transient fertility after vasovasostomy in 892 patients.

We report on the low incidence of transient fertility in 892 patients who underwent microsurgical vasovasostomy. Of the 892 patients in whom fertile sperm concentrations (as defined by us) developed 2 to 8 months postoperatively 28 later suffered azoospermia or severe oligospermia. The wives of 5 of the 28 patients with such transient postoperative fertility became pregnant before the patients became azoospermic or severely oligospermic again.