BACKGROUND:
Klinefelter syndrome is the most common chromosomal aberration in men with azoospermia. The revision of the Norwegian biotechnology law in 2004 allows infertile couples with this diagnosis to become genetic parents. Surgical sperm extraction has to be performed to enable identification of possible sperm production. The preliminary approval to use this procedure (stated in the biotechnology law) was extended in 2007. This paper presents a short overview of the infertility investigation and treatment in men with Klinefelter syndrome.

MATERIAL AND METHODS:
The paper is based on more than 10 years of clinical experience in workup and treatment of infertile couples with the diagnosis Klinefelter syndrome. In addition, a non-systematic search in Pubmed and Medline has been carried out.

RESULTS:
Use of a microscopy during testicular sperm extraction increases the possibility of finding sperm in men with Klinefelter syndrome. The microsurgical procedure also reduces the risk of complications. If the diagnostic recovery has identified testicular sperm, there is a high predictive value of finding sperm in a subsequent surgical procedure.

INTERPRETATION:
The optimal method for successful sperm recovery in men with Klinefelter syndrome implies the use of microsurgery. This surgical method should therefore be considered established.