Azoospermia

By RRM Academy Reviewed by Dr. Naomi Whittaker, MD, Board-Certified OBGYN, MIGS, NFPMC, FCI Updated May 14, 2026

Azoospermia is the complete absence of sperm in the ejaculate, confirmed on at least two separate semen analyses after centrifugation.¹ It affects approximately 1% of men in the general population and up to 15% of men evaluated for infertility. The condition is classified into two mechanistically distinct categories: obstructive azoospermia (OAZ) and non-obstructive azoospermia (NOA).

In obstructive azoospermia, sperm production is intact but outflow is blocked. Common causes include prior vasectomy, congenital bilateral absence of the vas deferens (CBAVD), epididymal obstruction, and ejaculatory duct obstruction. For men with post-vasectomy OAZ, microsurgical vasectomy reversal is the restorative option. It restores the anatomical pathway rather than extracting sperm for laboratory use. In non-obstructive azoospermia, impaired spermatogenesis is the underlying problem. Causes include testicular failure, chromosomal abnormalities, hormonal insufficiency, and, in some cases, correctable factors such as varicocele. Varicocele repair has improved spermatogenesis in select NOA patients, which is a restorative option worth evaluating before pursuing extraction.²

Surgical sperm retrieval (TESE or microTESE) can locate focal sperm production in some NOA cases, but the harvested sperm are used in ICSI. That is a bypass pathway, not a restorative one. Clinicians evaluating azoospermia within a restorative framework prioritize identifying correctable causes first. Both partners are assessed in parallel, since female factor evaluation shapes the urgency and direction of the male workup. and restorative andrology.

This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.