ICSI

What is Intracytoplasmic Sperm Injection (ICSI)?

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• Before a man’s sperm can fertilize a woman’s egg, the head of the sperm must attach to the outside of the egg.
• Once attached, the sperm pushes through the outer layer to the inside of the egg (cytoplasm), where fertilization takes place.

Sometimes the sperm cannot penetrate the outer layer, for a variety of reasons. The egg’s outer layer may be thick or hard to penetrate or the sperm may be unable to swim. In these cases, a procedure called intracytoplasmic sperm injection (ICSI) can be done along with in vitro fertilization (IVF) to help fertilize the egg. During ICSI, a single sperm is injected directly into the cytoplasm the egg.

How does ICSI work?

There are two ways that an egg may be fertilized by IVF: traditional and ICSI. In traditional IVF, 50,000 or more swimming sperm are placed next to the egg in a laboratory dish. Fertilization occurs when one of the sperm enters into the cytoplasm of the egg. In the ICSI process, a tiny needle, called a micropipette, is used to inject a single sperm into the center of the egg. With either traditional IVF or ICSI, once fertilization occurs, the fertilized egg (now called an embryo) grows in a laboratory for 1 to 5 days before it is transferred to the woman’s uterus (womb).

Why would I need ICSI?

ICSI helps to overcome fertility problems, such as:

• The male partner produces too few sperm to do artificial insemination (intrauterine insemination [IUI]) or IVF.
• The sperm may not move in a normal fashion.
• The sperm may have trouble attaching to the egg.
• A blockage in the male reproductive tract may keep sperm from getting out.
• Eggs have not fertilized by traditional IVF, regardless of the condition of the sperm.
• In vitro matured eggs are being used.
• Previously frozen eggs are being used.