Sperm Aspiration

Special Procedures for Sperm Aspiration

MESA, PESA, and TESE all sound like names of towns or acronyms for the space program. They are acronyms, but not for the space program. Each acronym represents the name of a specific procedure used to obtain viable sperm from the male reproductive tract to be used in ICSI assisted reproduction. ICSI stands for intracytoplasmic sperm injection and for many men with male factor infertility it is the only method they can use to sire their own child. The acronyms used at the beginning of this paragraph represent three procedures of sperm aspiration reserved for men who have the most severe types of male factor infertility, including no sperm in their ejaculate (azoospermia) or sperm that isn't moving or is dead (necrospermia).

Sperm Can Only Be Used for ICSI

Sperm harvested by any of the methods we will discuss here cannot be used for IVF insemination because there are not enough sperm retrieved to perform intrauterine insemination (IUI), no matter what process is used to gather the sperm. In order for sperm to qualify for IUI, at least five to eight million mature, motile (moving) sperm with normal morphology (shape and size) are needed for IUI. At best, sperm aspiration gathers enough to use for ICSI with some left over to freeze for another treatment of ICSI.

MESA

MESA is the acronym for microsurgical epididymal sperm aspiration. For men with a reproductive tract blockage, perhaps after a vasectomy or a congenital absence of the vas deferens, MESA is the optimal procedure to obtain sperm. It is a one-time procedure in which enough sperm is extracted to serve more than one ICSI treatment. The extra is necessary because most often pregnancy does not occur on the first try.

How MESA is Performed

MESA is performed by isolating the epididymis (the organ above the testicle where the sperm are stored) by using a ½ inch incision that is made in the scrotal skin. An operating microscope is employed in order to examine the tiny tubules of the epididymis that hold the sperm. A tubule is opened and the fluid inside is collected and examined to see if there is any sperm in it. All sperm containing fluid that is collected is taken to an IVF lab for processing, use and freezing. If the sperm that is collected is dead, or if there is no sperm in the location of the aspiration, then another part of the epididymis is examined. This process goes on until there is a large enough collection of sperm to use and store for future use as well.

The extra sperm collected is necessary in the event there is no pregnancy on the first ICSI initiative. It is also important if a couple is thinking ahead to more children. It is the safest of all sperm aspiration techniques and recovery is very fast. It is very cost effective and is now performed as an office procedure; however, the downside is that it is not readily available. MESA is usually offered only in places that specialize in male infertility because it requires highly trained medical staff to effectively perform the procedure.

PESA - Not the Best

PESA is a less expensive method of sperm aspiration than MESA. Using a needle inserted into the epididymis, the idea is to hopefully locate a pocket of sperm to aspirate. This system does not yield a high return when it comes to locating and aspirating sperm and there are rarely enough to use and freeze. It is a blind procedure in terms of the surgeon not being able to see exactly where the needle is going. If a blood vessel is hit accidentally, it will continue to bleed, producing a hematoma. The results are poorer with a higher rate of complications, making PESA less attractive to doctors.

TESE, The Second Choice

TESE, testicular sperm extraction is the second best way to collect sperm from men who have obstructive azoospermia. It is also the choice for men with non-obstructive azoospermia. This is an open procedure that is performed under full vision, which means there is less chance for complications. A small bit of testicular tissue is taken through a tiny incision in the skin. The tissue is separated into tiny pieces while in a culture liquid and the sperm are released from within the tubules as well as extracted from surrounding testicular tissue. The amount of tissue is not as much as is collected in MESA and the testicular sperm does not react to freezing as well as epididymal sperm does.