Objective: To review the results of postvasectomy testing when clearance was based on the absence of motile sperm and to compare them with regimens based on complete azoospermia.
Design: A review of 2,260 seminal assay results from 3,178 consecutive vasectomies performed during a 17-year period.
Setting: An outpatient vasectomy service in a private group practice in suburban Sydney.
Results: Clearance was given sooner and with less testing than with other reported regimens, without loss of reliability.
Conclusions: Testing can be done 4 weeks after vasectomy, regardless of the number of postvasectomy ejaculations. If specimens are examined within 12 hours of collection, clearance may safely be given if motile sperm are absent. Repeat tests are essential if any motile sperm remain but are not needed if only nonmotile sperm are found.
PIP: Between 1975 and 1992, a private physician performed 3178 vasectomies at the Cronulla Private Medical Clinic in Cronulla, New South Wales, Australia, and examined ejaculation specimens of 2260 of the cases either after 10 ejaculations or 4 to 14 weeks after vasectomy. He reviewed the postvasectomy testing results of those with immobile sperm and compared these results with those based on complete azoospermia. There were only 5 failures (0.16%) caused by either incorrectly performed vasectomy (1 case) or spontaneous recanalization (4 cases). A pregnancy revealed 1 failure (late recanalization and reappearance of motile sperm). Just 1.5% still had motile sperm during the first postvasectomy test. Further, the sperm count of these 33 men was less than 1 million sperm/ml and motility was either 5% or less. 9 weeks was the longest postvasectomy period with motile sperm still present. Sperm counts for specimens with no motile sperm varied from 1 to 33 million sperm/ml at 100 high power field, but the count for most cases was less than 1 million sperm/ml. Just 5 cases had 16 to 33 million nonmotile sperm. 19% of the men who returned for a sperm count 14 weeks after vasectomy still had some nonmotile sperm. Since nonmotile sperm cannot go through the cervical mucus or penetrate and fertilize the ovum, the physician gave the men with nonmotile sperm clearance, which was earlier than if he had waited for azoospermia. Therefore, testing can take place 4 weeks after vasectomy rather than after a set number of ejaculations, and if the specimens have no motile sperm within 12 hours of collection, the health provider can grant clearance. Further collection and publication of postvasectomy testing results are needed.