ICSI (intracytoplasmic sperm injection) is the most commonly used method of artificial insemination. It offers men who are struggling with considerable fertility problems the opportunity to realize the dream of having their own children.
When is ICSI performed?
This method is used when a man has poor sperm quality. Among the possible reasons why conception cannot occur are:
- Low sperm count
- Limited motility of the sperm
- Abnormal sperm
- Obstructive azoospermia (blocked ejaculatory ducts prevent sperm from entering the seminal fluid)
- Antisperm antibodies in the ejaculate
- Diseases, such as cancer, that mean only frozen sperm is available
Preparation for ICSI
Before the ICSI, the eggs of the woman are hormonally stimulated so that several fertilized eggs are available. During this process, specified quantities of the hormones FSH (follicle stimulating hormone) and LH (luteinizing hormone) are injected subcutaneously once a day. The injections can be made at home by the woman or her partner. Ultrasound scans are used to check whether the follicles have reached an appropriate size. If this is the case, the hormone HcG is administered to induce ovulation. 36 hours later, the eggs are removed transvaginally.
The sperm can be obtained either via masturbation or surgery. The latter is advisable in case of obstructive azoospermia, for example. In addition, it is possible to extract sperm cells directly from the epididymides (via MESA, microsurgical epididymal sperm aspiration). Masturbation takes place the day the egg is removed after no ejaculation has occurred for two to three days.
The removed eggs and sperm are then fused in a laboratory. The process of fertilization is carried out under a special microscope. Using a micropipette, the sperm is placed directly into the egg cell’s interior. How many of the eggs were able to be successfully fertilized is checked the following day.
The embryo transfer takes place approximately two to five days after fertilization. Two to five embryos (only the highest-quality embryos are used) are inserted into the uterus using a catheter. If multiple embryos are available, those that are not needed for the transfer can be frozen at a later stage. The procedure takes only a few minutes and takes place on an outpatient basis.
In about one percent of cases, ovarian hyperstimulation may occur due to the hormonal treatment. Symptoms include water retention, nausea, vomiting, diarrhea and breathing problems. The risk is greatest for younger and overweight women as well as those with PCOS. It also increases the chance of a multiple pregnancy. For this reason, only three embryos may be used per treatment.
Chances of Success
Per cycle, ICSI carries a 15 to 20 percent chance of pregnancy – similar to IVF. The advantage of this method is that the sperm is injected directly into the egg, while with IVF, the fertilization takes place in a glass vessel. Various factors such as age, underlying diseases and personal lifestyle play an important role in success. In addition, the chances of conception increase with the number of attempts.