Standard vs. ICSI Insemination
After oocytes are retrieved during In-Vitro Fertilization, there are two main insemination techniques. One is standard insemination, where the sperm and eggs are cultured together in a dish, and the sperm must penetrate the egg on their own, similar to natural insemination. The other way is intracytoplasmic sperm injection (ICSI), where the sperm are individually selected and placed inside the egg. There are many reasons why SDFC's reproductive endocrinologists and embryologists would recommend one or the other.
The first tool that is used to assess and create an insemination plan is the semen analysis. Many sperm quality parameters are checked in a semen analysis, but the concentration, motility, and morphology are most important when recommending an insemination plan. Drs Hummel and Kettel typically recommend standard insemination if these three factors are within normal limits. If any of these parameters are low, ICSI is the recommended treatment. This is because semen samples with a low quantity of sperm cells, motile sperm, or sperm normal in appearance may not be able to adequately penetrate and inseminate oocytes. With ICSI, patients with male factor can be assured that the sperm are placed inside the egg, and then it is up to them to fertilize!
The second method is based upon oocyte quality. Oocytes are surrounded by a protein shell, called the zona pellucida. Women who have lower quality oocytes, or who are considered advanced maternal age, typically have a hardened or pigmented zona pellucida. In this case, even a good quality sperm sample may have difficulty penetrating this hardened shell without the assistance of ICSI. Another important point regarding oocytes is their maturity. The maturity of the egg is important because it is those eggs that have the ability to be fertilized. Maturity can only be assessed by cleaning the eggs from their cumulus cells, which is only done when ICSI is to be performed. When the oocytes are to undergo standard insemination, the cumulus is not cleaned because these cells aid in the penetration process, and therefore, maturity is unknown. This is another consideration when deciding between standard and ICSI insemination. If oocyte maturity is thought to be low, or has been low in previous cycles, ICSI may be recommended.
The third assessment tool is patient history. When a patient has undergone IVF previously, fertilization results are an obvious indicator of how to proceed in a future cycle. Also, if a patient has conceived through intrauterine insemination, or even on their own, it is a clue that the sperm and eggs have what it takes to undergo standard insemination.
All of these assessment methods give clues to San Diego Fertility Center's physicians and embryologists on how the sperm and egg will interact. Patients are encouraged to take part in this discussion and understand reasons for the recommended insemination plan, and the advantages and disadvantages of both.