The head of the sperm must attach to the outside of the egg before it can fertilize a woman’s egg. Once attached, the sperm pushes through the egg’s cytoplasm to the interior, where fertilization occurs.

For a variety of reasons, the sperm sometimes fails to penetrate the outer layer. The sperm may not be able to swim or the egg’s outer layer may be thick or difficult to penetrate. In certain situations, intracytoplasmic sperm injection, often known as ICSI, can be used in conjunction with in vitro fertilization (IVF) to assist in fertilizing the egg. Due to the existence of sperm antibodies that may interfere with fertilization, ICSI treatment is advised where the male partner has undergone a vasectomy reversal, regardless of the sperm quality.

The female partner must undergo ovarian stimulation with fertility drugs as part of the treatment in order for several mature eggs to develop. After being aspirated through the vagina utilizing vaginal ultrasonography, these eggs are subsequently incubated in an embryology facility under controlled circumstances. By centrifuging, or spinning the sperm cells through a certain medium, the semen sample is prepared. This separates the majority of the dead sperm from the detritus and the living sperm. The single living sperm is then inserted into the egg by the embryologist using a glass needle.

Many patients choose to undergo the ICSI treatment to maximize their success even when the procedure is not clearly indicated.

When compared to non-ICSI embryos, the overall embryo quality obtained with ICSI embryos does not appear to differ. In a similar vein, there is no evidence that ICSI embryos and non-ICSI embryos differ in conception rates.