We examined preoperative factors that could predict successful microdissection testicular sperm extraction in men with azoospermia and nonmosaic Klinefelter's syndrome. We also analyzed the influence of preoperative hormonal therapy on the sperm retrieval rate.

Materials and Methods:

A total of 91 microdissection testicular sperm extraction attempts were done in 68 men with nonmosaic Klinefelter's syndrome. Men with serum testosterone less than 300 ng/dl received medical therapy with aromatase inhibitors, clomiphene or human chorionic gonadotropin before microdissection testicular sperm extraction. Preoperative factors of patient age and endocrinological data were compared in those in whom the procedure was and was not successful. The sperm retrieval rate was the main outcome. Clinical pregnancy (pregnancy with heartbeat) and the live birth rate were also calculated.


Testicular spermatozoa were successfully retrieved in 45 men (66%), representing 62 (68%) attempts. Increasing male age was associated with a trend toward a lower sperm retrieval rate (p = 0.05). The various types of preoperative hormonal therapies did not have different sperm retrieval rates but men with normal baseline testosterone had the best sperm retrieval rate of 86%. Patients who required medical therapy and responded to that treatment with a resultant testosterone of 250 ng/dl or higher had a higher sperm retrieval rate than men in whom posttreatment testosterone was less than 250 ng/dl (77% vs 55%). For in vitro fertilization attempts in which sperm were retrieved the clinical pregnancy and live birth rates were 57% and 45%, respectively.


Microdissection testicular sperm extraction is an effective sperm retrieval technique in men with Klinefelter's syndrome. Men with hypogonadism who respond to medical therapy may have a better chance of sperm retrieval.


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Center for Reproductive Medicine and Infertility, New York-Presbyterian Hospital, Weill Cornell Medical College, New York, New York