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Intracytoplasmic Sperm Injection (ICSI)

UPMC Content 2

Intracytoplasmic sperm injection (ICSI) is a form of micro-assisted fertilization.

In vitro fertilization (IVF) without ICSI involves mixing thousands of motile sperm with each egg in a Petri dish. We call this insemination of the eggs.

The sperm and eggs must then interact through biochemistry. The hoped-for result is fertilization of most of the eggs.

However, in some cases, either egg or sperm factors are deficient and very few (or none) of the eggs become fertilized after overnight incubation with sperm.

ICSI is a very effective procedure to assist fertilization for couples with sperm problems.

ICSI involves:

  • Selecting a sperm
  • Picking it up with a specialized micro-needle
  • Injecting it into the middle of the egg

We are trying to force fertilization for each egg, instead of mixing sperm and eggs together and hoping that they interact.

Our embryologists have extensive experience with ICSI and achieve high fertilization rates. The procedure allows men with little, or sometimes no, sperm in their ejaculate to create genetically related children.


  • After egg retrieval, the oocytes (eggs) are separated from the follicular fluid and placed in a Petri dish.
  • Approximately 1 hour later, the granulosa cells are stripped away from the egg. The eggs are examined under a microscope to assess maturity.
  • On all the mature eggs, a small hole is made in the zona pellucida (egg membrane) using microscopic tools and the sperm is inserted directly into the egg.
  • After insertion of the sperm (ICSI), the embryos are placed in incubators until ready for transfer.

Obtaining Sperm

ICSI requires that sperm be obtained from the ejaculate, if the male has sufficient quantity and quality of sperm.

When adequate sperm are not available, a MESA (microepididymal sperm aspiration) or a TESE (testicular sperm extraction) can be utilized.

MESA (microepididymal sperm aspiration)

ICSI combined with MESA is a noninvasive method of sperm recovery.

It has excellent potential for men who have had a vasectomy and do not wish to undergo surgical reversal, or had a failed surgical reversal. The success rates per cycle exceed those for a vasectomy reversal.

ICSI combined with MESA requires that a small needle be placed into the epididymis, using local anesthesia, to withdraw the sperm. The epididymis normally serves as a reservoir for sperm.

This technique would also be applicable for patients with:

  • Congenital absence of the vas deferens
  • Previous infection with resultant occlusion of the epididymis
  • Ejaculatory dysfunction due to multiple sclerosis or diabetes

TESE (testicular sperm extraction)

ICSI combined with TESE is useful:

  • For men who have non-obstructive azoospermia caused from maturation arrest disorders
  • When sperm could not be obtained through the MESA procedure

Using TESE, sperm are obtained by biopsy of the testicle.