Locating Sperm in the Testicles when there is Low Sperm Production
Testicular mapping (sometimes called sperm mapping) is a non-surgical technique has been developed to detect sperm in the testicles of men who have poor sperm production (non-obstructive azoospermia). Prior to the era of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), these men were considered sterile. With IVF and ICSI, the requirements for sperm have been reduced to 1 live sperm per egg. Many men who have been diagnosed with non-obstructive azoospermia either due to hypospermatogenesis, maturation arrest or sertoli-cell only syndrome (germinal cell aplasia) have been found to have small 'pockets' of sperm production within the testicles.
This observation has revolutionized an old concept that the testicle produced sperm in a uniform fashion and has led to the new concept of 'focal spermatogenesis'. Sperm production has been found in up to 70% of men who have FSH (follicle stimulating hormone) levels greater than three times the normal level or who had no sperm production on a past biopsy.