The ICSI procedure:
Once mature eggs have been obtained from the female the ICSI procedure is performed under a microscope using multiple specialized micromanipulation devices (micromanipulators, microinjectors and micropipettes) that enable the embryologist to select and then pick up individual sperm in the tiny, hollow ICSI needle. Once loaded with the single sperm, the hollow needle is pierced through the outer shell of the egg and egg membrane and the sperm is injected into the cytoplasm of the egg. After the procedure, the injected oocyte will be placed into cell culture inside an incubator and checked approximately 18 hours later for signs of fertilization.
Who should be treated with ICSI:
There is still debate amongst the infertility community as to exactly which cases should incorporate the ICSI procedure with IVF and which cases should use the older conventional method of fertilization whereby the egg is placed in the Petri dish surrounded by sperm and hopefully fertilization will take place unaided.
Over time, our thinking has evolved to the point where we use ICSI in all our cases so that we can maximize the number of embryos obtained per case. In our hands, using ICSI, we are achieving fertilization rates of greater than 90% and therefore we believe this excellent fertilization rate warrants the use of ICSI in all of our cases. At La Jolla IVF no additional fees are charged for ICSI because we consider ICSI to be a necessary adjunct of the IVF procedure in order to fully maximize the success of the cycle.
Sperm Retrieval Procedures:
There are a group of men for whom ICSI is mandatory because sperm cannot be obtained from their ejaculate. To bypass the problem of having no sperm in the ejaculate, several sperm retrieval procedures have developed.
In the late 1980’s it was shown that sperm obtained directly from the testes could be used to successfully fertilize eggs and achieve viable pregnancies. While this procedure was originally intended for men who were born with an obstruction in the genital tract (congenital absence of the vas deferens), later it was shown that men who had previous vasectomies could benefit from similar procedures as well.
With the progression of IVF and the subsequent development of ICSI, millions of motile sperm are no longer required to fertilize an egg. In fact now, an egg can be fertilized with a single non-motile sperm using the ICSI technique.
These more recent developments in IVF and ICSI have made several sperm retrieval techniques viable treatment options for males. Both men with anatomical blockages in their reproductive organs and those without enough sperm production to show any sperm in their semen analyses (but who are still making low levels of sperm in their testicles) may benefit from the various sperm retrieval procedures. Sperm may be retrieved from the male’s reproductive organs through a surgical incision or percutaneously through a needle.
Sperm Retrieval Techniques:
The four main sperm retrieval techniques are termed:
- Microsurgical Epididymal Sperm Aspiration or MESA
- Percutaneous Epididymal Sperm Aspiration or PESA
- Testicular Sperm Extraction or TESE
- Testicular Sperm Aspiration or TESA
Microsurgical Epididymal Sperm Aspiration (MESA):
An incision is made through the scrotal skin using optical magnification, the epididymal tubules can be incised and fluid with sperm is aspirated. A number of motile sperm are typically retrieved and can be used immediately for ICSI or can be frozen in several batches for delayed or subsequent cycles of IVF-ICSI should they be necessary. Occasionally, insufficient sperm is retrieved and a TESA procedure will need to be performed (see below).
Percutaneous Epididymal Sperm Aspiration (PESA):
A needle is passed through the scrotal skin into the epididymis in order to aspirate sperm. The epididymal tubule is delicate and convoluted and typically the yield of sperm retrieved is small with this procedure and usually only sufficient for a single cycle of IVF-ICSI performed on the same day as the PESA. Occasionally, sperm may not be reliably retrieved at all and an alternate procedure may need to be performed.
Testicular Sperm Extraction TESE:
The testicle is explored through a small scrotal skin incision. Small pieces of tissue are cut out of the testicle and sperm is extracted from this tissue. With this treatment sperm must typically be used with 24 hours of retrieval. In a patient with a blockage, there may be enough sperm to survive freezing of the tissue for later use.
Testicular Sperm Aspiration (TESA):
A needle is passed through the scrotal skin into the testicle. With syringe suction and numerous passes of the needle through the testicular tissue, a small amount of testicular tissue can be retrieved. In the case of obstruction, enough sperm would probably be obtained for a cycle of IVF-ICSI that day but not for freezing.
These various procedures are performed on an outpatient basis with various degrees of anesthesia ranging from local to general anesthesia. The recovery from the incisional procedures is similar to that of a vasectomy – 48 hours of limited activity and about one week of abstinence from sex or exercise. The recovery from a percutaneous procedure is easier and less restrictive.
These sperm retrieval procedures coupled with IVF-ICSI have enabled men with unreconstructable obstruction and men with extremely low sperm production with no sperm in their ejaculate to father children.
Suffice to say, artificial insemination by ICSI is one of the major breakthroughs in infertility treatment and has enabled thousands of children to be born around the world who would otherwise not be here.