Impact of microsurgical varicocelectomy on sperm capacitation and birth outcomes

To assess the impact of microsurgical subinguinal varicocelectomy on sperm capacitation, semen parameters, pregnancy rates, and live birth outcomes in men with clinical varicoceles.

We retrospectively reviewed 260 consecutive men with clinical varicoceles who underwent a microsurgical subinguinal varicocelectomy procedure by a single surgeon from January 2019 to March 2024. Of these, 46 men had pre- and postoperative semen analyses and sperm capacitation tests. The primary outcome measure was change in the sperm capacitation score (Cap-Score™; Androvia LifeSciences, Mountainside, NJ, USA). Secondary outcome measures included change in semen parameters, change in probability of generating a pregnancy (PGP), pregnancy rates, and live birth rates.

Among all 46 patients, there was an improvement in median sperm concentration (21.9 vs 30.0 million/mL; P < 0.01), mean total motile sperm count (TMSC; 33.9 vs 49.5 million; P = 0.04), mean sperm capacitation as measured by Cap-Score (23.6% vs 27.7%; P < 0.01), and mean PGP (27.4% vs 34%; P < 0.01) after varicocelectomy. Of the 33 couples trying to conceive, 24 (72.7%) achieved a live birth or ongoing clinical pregnancy after varicocelectomy; however, 13 of these 24 couples (54.1%) utilised in vitro fertilisation. A normal postoperative sperm concentration and Cap-Score were associated with a 60% chance of achieving pregnancy via natural conception or intrauterine insemination (IUI).

Significant improvements in sperm concentration, TMSC, Cap-Score, and PGP were observed at 3 months after surgery. Patients with a normal post-varicocelectomy Cap-Score and semen concentration had the highest probability of conception naturally or through IUI.