In vitro fertilization (IVF) is one of the most commonly used assisted reproductive technology (ART) techniques. It involves inducing ovulation by administering ovarian stimulating medication and retrieving eggs from the ovaries. The fertilized eggs are then implanted in the uterus using a catheter. Various other fertility treatments are also used in conjunction with IVF including intrauterine insemination (IUI), donor eggs and surrogacy.

MESA is a procedure to help men with vasal blockage of the penis and/or epididymis caused by s/p vasectomy or congenital bilateral absence of the vas deferens (CBAVD). MESA can be performed on its own or in conjunction with egg retrieval for the female partner of a couple undergoing IVF. Patients often have their sperm cryopreserved during MESA to be used in future IVF cycles.

The MESA process is done in the operating room under general anesthesia with the use of an operating microscope. A needle is inserted from the scrotum to the epididymis and the sperm ductules are dissected under magnification. A small amount of epididymal fluid is aspirated and sent to the laboratory for sperm extraction. If a large number of sperms are discovered another sperm ductule is resected and the duct closed.

MESA has had superior clinical pregnancy rates compared to aspiration methods. This is because MESA utilizes a microsurgical technique that ensures meticulous hemostasis during the retrieval and minimal contamination of epididymal fluid with blood cells. The success rate of MESA is even better when it is combined with ovulation-inducing medications such as gonal FSH, human chorionic gonadotropin and luteinizing hormone.  in vitro fertilization mesa