Sperm Retrieval is:
Sperm retrieval is a surgical techniques used to obtain sperm. The surgery is designed to help men who have extremely low or absent sperm levels in semen, a cause of male infertility that affects approximately 10% of all infertile men. That is necessary to extract sperm from the vas deferens, epididymis or testicles.
Sperm retrieval is used in conjunction with in vitro fertilisation (IVF) and in often cases with intracytoplasmic sperm injection (ICSI).

Effectiveness of Sperm Retrieval:
Sperm retrieval is a male infertility treatment that is most effective in cases following male infertility causes is affecting a couple’s chances of getting pregnant:

Sperm Retrieval techniques:
There are saveral methods of sperm retrieval to remove sperm from inside of the genital tract.All types of sperm retrieval procedures are considered to be minor surgeries and generally require a local anaesthesia as well as a recovery period of only a few days.

Percutaneous sperm aspiration (PESA): this type of surgery is most suitable for male infertility with the congenital absence of vas deferens or by the presence of scar tissue. This sperm retrieval procedure does not require surgery. The procedure is performed under local anaesthesia and usually takes 20 minutes.
In PESA, a needle is inserted through the scrotum via the epididymis. Doctors seek to collect 10 to 20 million sperm in sperm retrieval, that multiple aspirations in one or both testicles are necessary. Sperm removed from the epididymis in one or both sperm are not yet mature, that the use of ICSI is necessary in order to fertilize an egg for pregnancy to occur.
Vasal aspiration: this infertility treatment is used when the vas deferens is blocked or in cases a vasectomy was performed within the last five years. Vasal aspiration is the only type of sperm retrieval that is able to retrieve mature sperm, as the sperm removed in this procedure has travelled through the epididymis. This procedure requires a local anesthesia; a needle is inserted into the vas deferens and is massaged to produce additional liquid before being removed. The extracted sperm is then prepared for IVF. Because mature sperm is collected, it can also be cryogenically preserved for future use, in addition to being used in conjunction with ICSI.
Micro-epididymal sperm aspiration(MESA): this form of sperm retrieval requires a tiny incision through the scrotum and into the epididymis. Fluid found in the epididymal tube is drained and then analyzed for the presence of sperm. This type of male infertility treatment procedure is performed under a general anaesthesia and is used to treat men who have scar tissue present on the vas deferens, or for men who do not have a vas deferens.
Testicular sperm extraction (TESE): best suited when the cause of male infertility is due to a blockage in the epididymis that is found close to the testicles, thereby preventing sperm from entering into the epididymis. It is also used to treat male infertility problems when a blockage in the testicles or when sperm count is low enough so that sperm cannot reach the ejaculate that is preventing a couple from getting pregnant.
In this surgical male infertility treatment procedure, immature sperm is removed directly from the testicles through a testicular biopsy, which removes some testicular tissue. A local anesthetic is administered and a small incision is made in order to remove tissue.

Risks of sperm retrieval:
There are no major risks associated with sperm retrieval. The main can include bleeding and infection, however, this is quite rare and occurs in approximately 3% of patients. Any procedure that requires an anesthetic will carry an increased risk of complications.

Success rates of Sperm retrieval :
PESA has the highest rate of success in the retrieval of sperm, 80 to 90% while TESE has a sperm retrieval success rate of 60%.
Depending on the type of surgery, sperm retrieval linked to a pregnancy success rate of approximately 20 to 30%. MESA is linked to a higher pregnancy rate when used in conjunction with ICSI, between approximately between 36% and 56%. TESE is linked to a 20% rate of pregnancy success while PESA is linked to a pregnancy success rate of about 26%.