MESA (Microsurgical Epididymal Sperm Aspiration)
Microsurgical Epididymal Sperm Aspiration (MESA)
MESA is an open surgical sperm retrieval procedure that uses an operating microscopy to locate the tubules of the epididymis precisely, so that large numbers of sperm can be extracted.
MESA is a procedure performed for men who have vasal or epididymal obstruction (s/p vasectomy, congenital bilateral absence of the vas deferens). It is either done as a scheduled procedure or is coordinated with their female partner’s egg retrieval.
MESA is done in the operating room with general anesthesia under the operating microscope. MESA involves opening the testicle by an incision after locating the epididymis and then aspirating the sperm directly from the epididymis with a fine needle. One aspiration may provide enough sperm for several attempts at IVF using ICSI. MESA can be performed well in advance of any proposed IVF procedure. Patients usually cryopreserve sperm during this procedure for future IVF/ICSI. MESA allows an extensive collection of mature sperm as compared to aspiration techniques, and it is the preferred method of retrieval for men with congenital bilateral absence of the vas deferens as it does not impact steroid production of the testis.
Patients frequently have donor sperm backup in case sperm are not found in the male partner.
You have the following options in case sperm is not found by MESA:
1. Egg retrieval of the IVF might be cancelled if the doctor sees no harm in cancelling it or the egg retrieval can be done without fertilization, and then the eggs can be destroyed.
2. Eggs retrieved can be frozen for later use.
3. Fertilize the eggs by sperm donation.

