MESA technique is used for men with no sperm in their semen because of a blockage or an absence of the vas deferens (the tube which leads from the testis).
There is a group of men who have no sperm in their semen because of a blockage or an absence of the vas deferens. The vas deferens is a tube, which leads from the testis towards the penis; sperm must travel down this tube to leave the body. Such men may be producing sperm in large numbers, but because there is a blockage or absence of the vas deferens none will be seen in the semen. This is similar to a man who has had a vasectomy.
In these cases sperm can be obtained from the epididymis, which is an organ which is located on top of the testis where sperm collect and mature. If the epididymis itself is blocked or absent sperm can be extracted from the testicles.
Assisted Reproductive Technologies (ART) are techniques which bring the sperm closer to the egg.
In many cases, a treatable cause of Male Infertility has not been identified or treatment has not resulted in pregnancy. ART or assisted reproductive technologies may be sued to bring and place the sperm closer to the egg with the hope that this will achieve a pregnancy.