Intracytoplasmic sperm injection (ICSI) is a treatment for male infertility that revolutionized the field of fertility medicine and gave hope to a vast number of couples who had given up all hope of becoming biological parents. ICSI was first introduced in 1992. The procedure involves extracting just one sperm that has good motility and then injecting this sperm into the woman's egg which begins the process of fertilization. ICSI is used in tandem with in vitro fertilization (IVF).
According to the Society for Reproductive Medicine the fertilization rate for ICSI is from 50%-80% but some clinics may have a fertilization rate of up to 85% with this method. In the year 2006, 34% of all U.S. ICSI cycles succeeded in producing a live delivery. Up to 60% of all cycles employing assisted reproductive technology in the U.S. involve the use of ICSI.
Paul Turek, MD, states that the basic IVF procedure needs a minimum of 500,000 sperm per egg. But he adds that there are many infertile males who don't produce even this minimal amount of sperm. Turek directs the male reproductive laboratory at the San Francisco-based University of California.
This is where ICSI comes in. The procedure is now commonplace in IVF treatments where the man has a very low sperm count, or has sperm with poor motility (movement). A low sperm count may be due to an absence of the vas deferens (a pair of tubes that can carry sperm from the testicles to the penis), or because of some kind of damage to the reproductive organs. In these cases, ICSI is able to extract the sperm so that it can be used in an IVF procedure. Even those men who have had vasectomies or men thought to be sterile as a result of aggressive cancer treatment are considered perfect candidates for ICSI. As Turek explains, ICSI enables sperm that cannot be ejaculated to be extracted so as to fertilize eggs.
Some couples, however, are choosing ICSI because they believe it enhances their rates of success with IVF. This is even truer in the case where the woman has produced only a limited number of eggs.
In ICSI, the female part of the couple will need to take medication to trigger her ovaries to manufacture a large number of mature eggs. Using a transvaginal ultrasound-guided needle, the technician harvests the woman's eggs from her ovaries. These eggs are then placed in a petri dish for fertilization with sperm.
If it is found that the male partner's semen doesn't have enough moving sperm, a physician can use a needle to extract the sperm from a testicle. If this sample still has too few sperm, a sample of testicular tissue may be taken in which, it is hoped, there will be some sperm. This is a painful procedure necessitating anesthesia.
Once motile sperm have been identified, a single sperm will be injected into each egg. If fertilization takes place, the eggs will remain in Petri dishes for a few days of division. With the help of a thin catheter, these embryos are then implanted into the uterus!