Intracytoplasmic Sperm Injection (ICSI) is primarily used to treat male factor infertility. For men who have just a few, barely swimming sperm in the ejaculate or even for males who fail to ejaculate any sperm, the ICSI procedure can be used to directly inject a sperm into each egg.

ICSI Process

ICSI is often combined with a sperm harvesting technique such as Microsurgical Epididymal Sperm Aspiration (MESA) and Percutaneous Epididymal Sperm Aspiration (PESA), an office procedure where sperm is obtained by passing a tiny needle through the skin into the epididymis. Testicular Sperm Extraction (TESE), also an office procedure, is now sometimes done with a large biopsy needle under local anesthesia, rather than being done as a full surgical biopsy. In some cases where the lack of ejaculated sperm is due to poor sperm production, a sophisticated technique can be done where the testicle is opened and a microscope is used to identify the few tubules that in some of the men contain viable sperm (microTESE).


The IVF cycle with ICSI is conducted similarly to a non-ICSI cycle, with a few exceptions. After the eggs are retrieved, instead of mixing the sperm with the egg, the embryologist uses a thin glass pipette to immobilize the sperm, draws it into the pipette and then injects it directly into the egg’s cytoplasm. Since the egg is the size of a pinpoint, it is a sophisticated technique requiring a high-powered microscope, tiny glass pipettes and instruments that translate hand movements into extremely fine movements of the pipettes.

Success Rates

The success rate for IVF with ICSI is approximately the same as for IVF, indicating that the manipulation has very little effect on the egg. However, since the female partners of these men are often reproductively normal, there may be some small adverse effect, also reflected in reports of slightly reduced embryo quality with ICSI. Most data indicates similar rates of congenital abnormalities compared with the general population and IVF without ICSI, although some reports suggest a minor increase of chromosomal anomalies, many of which are related to the man’s genetics or his sperm. Because of these concerns, prenatal genetic testing of fetal chromosomes (a karyotype) is suggested for ICSI pregnancies. Recently, there have been concerns about a higher rate of some rare abnormalities which may be associated with IVF and ICSI, specifically Beckwith-Wiedemann syndrome which includes kidney problems, low blood sugar and an increased risk of childhood tumors.

In a proportion of men (10 – 20 percent) with very low or absent sperm in the ejaculate, the man may have a chromosome defect or a genetic defect not visible on routine chromosome analysis (Y chromosome microdeletion) that could pass on a similar infertility problem to male offspring. Rarely, such a chromosome defect could cause a serious abnormality in the offspring. We suggest a pre-cycle karyotype for men with fewer than 5-10 million sperm per ml in the ejaculate. In men with congenital absence of the vas deferens, one can assume the male is a carrier for Cystic Fibrosis (CF). These men may have a mutation not screened for in the standard CF panel, so testing the female partner is recommended and using an extended panel is a must. If she is a carrier, the couple could elect to have a sample of placental tissue (chorion villous sampling or CVS) or of amniotic fluid (amniocentesis) and to abort a CF fetus. Fortunately such couples can instead have PGD where cells are analyzed from each embryo and only unaffected embryos are transferred.