Prognostic factors for sperm retrieval in non-obstructive azoospermia

Testicular sperm retrieval techniques associated with intracytoplasmic sperm injection have changed the field of male infertility treatment and given many azoospermic men the chance to become biological fathers. Despite the current use of testicular sperm extraction, reliable clinical and laboratory prognostic factors of sperm recovery are still absent. The objective of this article was to review the prognostic factors and clinical use of sperm retrieval for men with non-obstructive azoospermia. The PubMed database was searched for the Medical Subject Headings (MeSH) terms azoospermia, sperm retrieval, and prognosis. Papers on obstructive azoospermia were excluded. The authors selected articles that reported successful sperm retrieval techniques involving clinical, laboratory, or parenchyma processing methods. The selected papers were reviewed, and the prognostic factors were discussed. No reliable positive prognostic factors guarantee sperm recovery for patients with non-obstructive azoospermia. The only negative prognostic factor is the presence of AZFa and AZFb microdeletions.