Prognostic value of the clinical and laboratory evaluation in patients with nonmosaic Klinefelter syndrome who are receiving assisted reproductive therapy.

Objective: To characterize clinical and laboratory findings in nonmosaic 47,XXY patients that may help to predict spermatogenetic activity in their testicles.

Design: Prospective study.

Setting: Assisted reproductive technology program.

Patient(s): Twenty patients with nonmosaic Klinefelter syndrome who underwent testicular sperm retrieval for IVF.

Main Outcome Measure(s): The correlation between basal FSH, LH and testosterone levels, mean testicular volume, and results of the hCG test and presence or absence of sperm after testicular sperm extraction (TESE).

Result(s): Sperm was found in nine patients (45%). The mean testicular volume was 7.8 +/- 2.5 mL in men with sperm after TESE and 5.6 +/- 1.2 mL in those without sperm after TESE; corresponding testosterone levels were 3.5 +/- 1.2 ng/mL and 1.7 +/- 0.8 ng/mL. Serum levels of FSH and LH did not significantly differ between groups. After the hCG test, the mean serum testosterone level was 16.0 +/- 6.3 ng/mL in men with sperm after TESE and 6.7 +/- 5.6 ng/mL in those without sperm.

Conclusion(s): Testicular volume, testosterone levels, and results of the hCG test are important predictive factors of spermatogenesis in patients with nonmosaic Klinefelter syndrome.