What predicts successful sperm retrieval in micro-TESE?

[Verified against AUA/ASRM Male Infertility Guideline 2021] Technique first, because it is the most robust finding. For men with NOA undergoing sperm retrieval, microdissection TESE should be performed (Moderate Recommendation, Evidence Grade C). Meta-analysis found micro-TESE successful 1.5 times more often than non-microsurgical TESE, and TESE 2 times more likely to succeed than testicular aspiration. Micro-TESE also has less effect on testosterone levels than conventional TESE, though testosterone deficiency requiring replacement remains a risk even after micro-TESE. Genetic predictors are the most decisive: Complete AZFa and/or AZFb deletion — sperm have not been retrieved by TESE. Surgical intervention is not indicated. This is the one predictor that should stop the procedure being offered. AZFc deletion — sperm retrieved in at least 50%. Klinefelter 47,XXY — rare foci of spermatogenesis found in at least 50–60%. The guideline does not endorse FSH, testicular volume or inhibin B as reliable individual predictors of retrieval success in NOA, and men and their partners should be counselled accordingly rather than given a percentage derived from those parameters. On sperm handling: either fresh or cryopreserved sperm may be used for ICSI (Moderate Recommendation, Grade C). For OA there is no substantial difference, so retrieval and cryopreservation can precede ART. For NOA some centres synchronise retrieval with the ART cycle, because sperm numbers may be limited and may not survive cryopreservation. Reviewer: if you wish to quote centre-specific retrieval rates, cite your own audit data rather than published series.