A predictive score for testicular sperm extraction quality and surgical ICSI outcome in non-obstructive azoospermia: a retrospective study

BACKGROUND: In non-obstructive azoospermia (NOA), testicular sperm extraction (TESE) is successful in similar to 50% of cases. A parameter for predicting TESE quality and pregnancy rates after ICSI of testicular spermatozoa is still lacking. METHODS: We retrospectively evaluated the total testicular volume (TTV), hormone levels and TESE quality in 280 patients with NOA. After successful TESE, the characteristics of the ICSI cycles and the take-home baby rates were evaluated. RESULTS: TESE was successful in 149 patients (53.2%). In a multivariate logistic regression analysis, only TTV, FSH and inhibin B were correlated with the TESE outcome. A score including these three parameters was the best predictor of successful TESE (positive likelihood ratio: +3.01). When the score was < 18.5, TESE was successful in 77.4% of cases and 'sperm rich' (i.e. yielding > 100 spermatozoa) in 91.1% of cases; 42.8% of couples took a baby home. The take-home baby rate did not depend on whether the score was < 18.5 or between 18.5 and 3700. If the score was > 3700, TESE was successful in 37.8% of cases and 'sperm rich' in 14.3% of cases; only one couple took a baby home (a rate of 7.7 versus 42.8% when the score was < 18.5; P < 0.001). Owing to low sperm retrieval on the day of oocyte retrieval, fewer oocytes were injected when the score was >3700 than when <3700. CONCLUSIONS: Thanks to better knowledge of TESE quality, the present score could help to improve care and pre-ICSI counseling for patients with NOA.