When discussing fertility treatments or IVF, people often mention sperm extraction (medical removal of sperm), but few really know what that means. We all know about the obvious methods, specifically sex, but actually when trying for a baby with medical help there’s slightly more to it.
There are 4 main types of sperm extraction: Percutaneous Epididymal Sperm Aspiration (PESA), Testicular Sperm Aspiration (TESA), Testicular Sperm Extraction (TESE) and Micro Epididymal Sperm Aspiration (MESA) and Microdissection TESE (microTESE). All perform different but equally important roles. They are commonly performed by a gynaecologist or urologist on men who do not produce sperm in their ejaculate, a condition referred to as Azoospermia, or in very rare circumstances to remove sperm from men following an untimely death.
Sometimes it is difficult to compute what each of these are when talking to your fertility specialist, or even to understand why certain ones will work better for you.Here is a quick guide to help. (The image is a simple side view diagram of the testis and relevent parts illustrating where sperm extration can occur.)
1. Percutaneous Epididymal Sperm Aspiration (PESA)
PESA is recommended for men who have no sperm in their ejaculate as a result of an obstruction, a condition known as Obstructive Azoospermia. This can be caused either as a result of a prior vasectomy operation or by an infection. It is generally performed with local anesthesia and a needle aspiration is made in the epididymis (the body of the testis) where sperm is stored prior to ejaculation. This is a simple procedure and in many cases a large number of moving sperm can be obtained.
2. Testicular Sperm Aspiration (TESA)
TESA is a proceedure commonly performed on men who have no sperm in the semen and are undergoing a diagnostic investigation to determine if they are producing sperm in the testicles. A fine needle is inserted in the testicle and tissue, containing the seminiferous tubules, is aspirated. This technique is very useful for exploring multiple sites within the testicular body with minimal trauma. It can also be used to locate and retrieve sperm from Azoospermic men who may only have a small functioning pocket of sperm production within the testicular body. The sperm can then be used to inject into the eggs of their partner using intra cytoplasmic sperm injection to achieve fertilization.
3. Testicular Sperm Extraction (TESE)
TESE involves making a small incision in the testis and removing a piece of testicular tissue. The technique allows for a much larger amount of tissue to be recovered and is often the preferred approach when Azoospermic men are being treated with their partners for infertility. TESE is usually performed in the operating room with sedation or using a local anesthetic.
4. Micro Epididymal Sperm Aspiration (MESA) and Microdissection TESE (microTESE)
Both of these techniques are performed in the operating room by a urologist with general anesthesia utilizing the operating microscope.
In fertility clinics PESA, TESA or TESE are commonly the preferred approaches for extracting sperm from Azoospermic men. They can be performed during a routine operating list and any skilled embryologist will be able to perform a diagnosis on the tissue, remove sperm for treatment or freeze it for later use.