Intracytoplasmic Sperm Injection (ICSI)
ICSI or Intracytoplasmic Sperm Injection. During the traditional IVF procedure, around 50,000 to 100,000
motile sperms are placed for each egg in the media for in vitro fertilization. with the hope that one of the
sperm will enter and fertilize the egg by itself. However, with ICSI-IVF, the embryologist takes a single
sperm and injects it directly into an egg to increase the chances of fertilization. This happens in situations,
wherein the sperm cannot penetrate the outer layer, which could be for a variety of reasons. Either the
egg’s outer layer would be thick or too hard to penetrate, or even the sperm would be unable to swim. In
such cases, ICSI is done along with in vitro fertilization (IVF) to enable egg fertilization.
How does ICSI work?
There are two ways in which an egg can be fertilized through IVF- the traditional method and ICSI. In the
traditional IVF method, more than 50,000 swimming sperm are placed next to the egg in the media in an
incubator in the laboratory. When one of the sperm enters into the cytoplasm of the egg the Fertilization
occurs.
However, in the case of the ICSI process, a micropipette (a tiny needle), is used to inject a single sperm
directly into the center of the egg. With either traditional IVF or ICSI, once the fertilization occurs, the
fertilized egg which is now called an embryo grows in the media in the laboratory for some 1 to 5 days,
post it is transferred to the woman’s uterus.
When is ICSI required?
ICSI can essentially help overcome multiple fertility issues such when:
Eggs do not get fertilized by traditional IVF, regardless of sperm condition.
The In-vitro matured eggs are being used.
A blockage in the male reproductive tract keeps sperm from getting out. (obstructive azoospermia)
The male partner produces too few sperm to do artificial insemination (intrauterine insemination [IUI]) or
IVF. (Severe oligozoospermia)
Previously frozen eggs are utilized.