ICSI vs. IVF
ICSI and IVF are two scientific processes of fertilization that are similar in some ways and quite different in others. Both procedures help couples struggling with infertility achieve fertilization and expand their families. The two procedures are different, however, in the methods used to achieve this fertilization.
In vitro fertilization (IVF) combines eggs and sperm outside the body. Reproductive specialists collect eggs and sperm, known as gametes, from each partner. Then, in a process known as insemination, the embryologists put the gametes together in a special dish and place that dish in a special chamber.
The sperm swims around the dish and attempts to enter and fertilize any egg they happen to encounter. The sperm generally fertilizes the egg a few hours after insemination, according to the National Library of Medicine. Once the embryo or embryos form, usually about three to five days after insemination and fertilization, a doctor will use a long tube to place the embryos in the uterus.
The major drawback to the IVF procedure is that it relies on large numbers of actively swimming healthy sperm for fertilization to happen. ICSI provides hope for couples who struggle with infertility caused by or complicated by low sperm count and low sperm motility.
Intracytoplasmic Sperm Injection (ICSI)
Intracytoplasmic Sperm Injection (ICSI) is very similar to the conventional IVF procedure in that doctors collect eggs and sperm from the partners. The major difference is that, rather than combining the gametes together in a dish and simply hoping the sperm will encounter the eggs, embryologists inject the sperm directly into the egg.
In the ICSI procedure, the embryologist uses a fine glass needle to pick up single sperm and inject it directly into each egg. Only highly trained and experienced embryologists using technically advanced equipment do this procedure. ICSI requires the use of very few sperm, and these sperms do not have to swim well or be able to penetrate the egg because the embryologist does all the work for them.
While ICSI does guarantee that the sperm gets ready access to the egg, it does not guarantee that fertilization will occur once the sperm is placed inside the egg.
From the patient’s point of view, undergoing an ICSI treatment cycle is essentially the same as going through a conventional IVF cycle; the patient performs the same steps in each procedure.
ICSI may be the appropriate procedure in cases where the sperm count is very low. It is also helpful when the sperm does not move properly or are abnormal in other ways. Embryologists may perform ICSI in cases where reproductive specialists have retrieved the sperm surgically from the man’s testes, from urine, or following a sperm collection procedure is known as electro-ejaculation. ICSI may be appropriate in cases where there is a high level of antibodies in the semen.
ICSI may also be appropriate in cases where the conventional IVF procedure failed to result in fertilization.
For more information on ISCI versus IVF, consult with your local fertility clinic.