Background

Testosterone therapy (TT) is known to have a contraceptive effect on sperm production.¹ Exogenous testosterone administration initiates negative feedback on the pituitary, dampening both follicle-stimulating hormone and luteinizing hormone release from the anterior pituitary. Consequently, signaling of endogenous testosterone production and testicular spermatogenesis is diminished, often resulting in severe oligospermia or azoospermia within the ejaculate.¹ Among men who have undergone vasectomy, using the ejaculate as an indicator as to the specific impact of TT on spermatogenesis is challenging as the occlusive nature of the vasectomy in and of itself leads to azoospermia.

During vasectomy reversal (VR), accurate intraoperative microscopic assessment of the vasal fluid for sperm presence and quality is essential in determining the indication for a vasovasostomy (VV) or vasoepididymostomy (VE).² Contemporary guidelines (American Society for Reproductive Medicine)³ generally recommend that a VV be performed if the presence of sperm or sperm parts are identified within the aspirate of fluid expressed from the testicular end vas, whereas a VE is indicated if no sperm are identified within the vasal fluid; a noted exception, favoring VV, is the absence of sperm within clear and copious vasal fluid. The suppressive impact of TT on testicular sperm production can potentially interfere with this determination and theoretically lead to erroneous intraoperative decision-making. For example, in a patient on TT at the time of VR, the absence of sperm within an intraoperative fluid aspirate from the testicular end vas could be indicative of either epididymal obstruction or diminished spermatogenesis consequent to TT in the absence of epididymal obstruction. Consequently, the absolute indication for VV or VE would be uncertain.

The objective of the current initiative was to evaluate the impact TT on vasal and epididymal fluid sperm characteristics, intraoperative decision-making, and postoperative outcomes among men on TT at the time of VR.

Methodology

A prospective patient data series of VR surgeries performed by a single surgeon (EG) between 2007 and 2023 was analyzed. Of 2,622 consecutive VRs, patients actively using TT at the time of VR were identified and details as to the type, dose, and duration of TT were documented. Prior to reversal surgery, all patients were counselled regarding the potential impact of TT on spermatogenesis and encouraged to discontinue TT if possible.

During VR, vasal fluid was manually expressed and sampled from the freshly transected testicular end vas and the vasal fluid quality was characterized (thick paste/opaque/translucent/clear). The vasal fluid volume was documented as copious/minimal. Immediately following vasal fluid aspiration, each sample underwent intraoperative bench microscopic evaluation at 200 power to determine sperm presence (yes/no) and vasal sperm quality—categorized as motile sperm/intact nonmotile sperm/sperm parts (sperm heads or tails)/no sperm.³ As indicated, fluid from the epididymal tubules was similarly analyzed and categorized. Testis tissue biopsy was performed only among patients demonstrating an absence of sperm within both the vasal and epididymal fluid samples.

Rates of sperm presence/absence in the vasal/epididymal fluid, frequency of VV/VE, postoperative patency (presence of motile sperm in the ejaculate), and semen parameters were compared among patients on TT vs clinically matched patients not using TT at the time of VR.

Results

Among the 2,622 VRs performed during the study time frame, 54 men (2%) reported using TT at the time of their VR. All patients reported biological fatherhood prior to both their VR and initiation of TT. Despite the impact of testosterone on spermatogenesis, intraoperative microscopic analysis of the reproductive fluid (vasal or epididymal) identified the presence of sperm in 95% (51/54) of all patient subjects. Among these patients, 86% (44/51) had sperm identified within the vasal fluid and had a VV performed, while the remaining 14% (7/51) of men had evidence of sperm within the epididymal fluid aspirate and underwent VE. Testis biopsy confirmed sperm production among the 3 (5%) patients with an absence of sperm within both the vasal or epididymal fluid. Among these patients, all had a VV completed. Collectively, 100% of men on TT demonstrated evidence of spermatogenesis at the time of VR.

Compared to clinically matched nonusers of TT, rates of VV or VE did not significantly differ among men using TT at the time of VR. Postoperative patency rates (TT: 78% vs no TT: 93%) and mean total motile sperm counts were lower among patients using TT at the time of VR (TT: 7.9 vs no TT 28.3, P = .02).

In conclusion, the use of TT at the time of VR does not appear to impact rates of intraoperative microscopic identification of sperm within the reproductive fluid or the indication for VV or VE. Compared to patients not using TT, postoperative patency rates and total motile sperm counts may be lowered by use of TT. Moreover, the determination to the etiology azoospermia postoperatively (production vs obstruction) may be clouded by the use of TT during VR.

Support: None.