Preliminary results of a prospective study of testicular sperm extraction in young versus adult patients with nonmosaic 47,XXY Klinefelter syndrome.

Context: Testicular sperm extraction (TESE) in adult patients with nonmosaic 47,XXY provides a sperm retrieval rate (SRR) of approximately 50%. Age is the only significant prognostic factor. Whether TESE should be performed in adolescent patients for sperm cryopreservation remains to be determined.

Objective: The objective of the study was to compare SRR between young (15-23 y) and adult (> 23 y) patients with 47,XXY, and to determine whether previous androgenic treatment had a deleterious effect.

Design: We designed a prospective comparative study between two groups enrolled in parallel from September 2010 onward.

Setting: University hospital.

Patients: Forty one patients with nonmosaic 47,XXY karyotype and azoospermia were included. Twenty five patients from 15-22 years of age were assigned to the "Young" group, and 16 patients age 23 years or more, to the "Adult" group.

Intervention: A bilateral testicular open biopsy was performed by a single surgeon. The reproductive biologist who performed TESE was blind to the patient's age. Principal Outcome Measure: The main outcome measure was the SRR. The TESE procedure was considered positive if at least 20 sperm cells could be cryopreserved for intracytoplasmic sperm injection.

Results: SRR was 13/25 = 52% in the Young group and 10/16 = 62.5% in the Adult group, the difference being nonsignificant (P = .73). Ages were 24.3 ± 7.4 years in the 23 cases of positive TESE, and 23.7 ± 7.4 in the 18 cases of negative TESE, the difference being nonsignificant (P = .42). SRR was 9/17 = 52.9% for patients with and 14/24 = 59.1% for patients without previous testosterone (T) treatment, the difference being nonsignificant (P = .98).

Conclusions: According to the present results, performing TESE at a younger age (15-23 y) in patients with azoospermic nonmosaic 47,XXY Klinefelter did not increase SRR relative to adult patients (25-39 y). Previous replacement treatment with moderate doses of T did not seem to be deleterious for the recovery of sperm cells by TESE.