Weill Medical College
Cornell Institute for Reproductive Medicine
Center for Male Reproductive Medicine and Microsurgery
"State-of-the-Art Compassionate Care for the Infertile Couple"
As mentioned above, it was previously thought that sperm retrieved from the testis were incapable of fertilization. However, fertilization and subsequent pregnancies with testicular sperm have been reported by several authors who used open or percutaneous methods to retrieve sperm directly from the testis. The limited experience to date with percutaneous testicular retrieval of sperm makes critical evaluation difficult. Silber et al. have reported that ongoing pregnancy rates with sperm retrieved from the testis for use with IVF/ICSI are similar to results achieved with sperm retrieved from the epididymis (43 versus 50 percent, respectively). They conclude that when epididymal spermatozoa cannot be retrieved, a testicular biopsy can be performed and the few barely motile spermatozoa obtained can be used for ICSI.
To summarize, the advantages of fine needle aspiration of the testis and percutaneous aspiration of the epididymis are that they can be performed with less anesthesia, without open scrotal exploration and its attendant postoperative discomfort for the patient, they are easily repeatable and potentially less expensive than microsurgical techniques, and the procedures do not require specialty training in microsurgery. The disadvantages are, most importantly, the low pregnancy rates achieved to date (24 percent compared to 50 to 52 percent achieved with MESA and IVF/ICSF, the limited ability to cryopreserve sperm for future IVF/ICSI procedures, the potential for damage to adjacent tissue, the relatively poor quality and low numbers of sperm retrieved per aspiration, and the frequent contamination of sperm with blood cells.