Intracytoplasmic Sperm Injection
In Vitro Fertilization
Intracytoplasmic Sperm Injection (ICSI)
revolutionized the treatment of male
factor infertility. It allows men who were previously
incapable of producing offspring, to father genetically
related children. ICSI involves the placement of a
single sperm directly into the egg using a microscopic
Men normally produce millions of sperm in each ejaculate. These sperm swim through the cervical opening and into the uterus to the site of fertilization at the end of the fallopian tubes. Some men have sperm defects, such as a reduced sperm count, deformed sperm, or sperm that cannot swim effectively. When any one of these abnormalities is present normal fertilization can be impaired.
ICSI bypasses sperm defects because
a single sperm is "selected" and injected
directly into the egg. ICSI is performed as a part
of an IVF cycle.
During IVF, the eggs are retrieved
from the ovaries and taken to the embryology laboratory.
In ICSI, a stereomicroscope is used to manipulate
the egg(s). The egg is held in place while it is punctured
by the micropipette and the sperm is inserted.
IVF/ICSI is used in cases of moderate
to severe male factor
infertility and in other conditions such as failed
fertilization in previous IVF cycles. It is also indicated
in advanced female age, when the ability of the egg
to be naturally fertilized is in question, and in
some cases of unexplained infertility.
ICSI can be effective when no sperm are present in the male's ejaculate. In these cases, a few sperm can often be retrieved from the male's testis or the lining of the reproductive tract in a minor surgical procedure conducted in our facility by a urologist. The procedure is accompanied by minimal discomfort.
Microscopic epididymal sperm aspiration (MESA) and testicular sperm aspiration (TESA) are both procedures for obtaining sperm from the male reproductive tract. TESA involves extracting sperm directly from the testicle and is utilized in severe male factor cases. MESA involves extracting sperm from the epididymis (tube that transports the sperm).
These approaches are very successful in men who have undergone a vasectomy and wish to avoid surgical reversal. Other candidates include men with congenital absence of the vas and others with testicular failure that may produce viable sperm on exploration of the testicle.
Studies to date have indicated no increase in birth defects. There may be a slight increase in sex chromosome abnormalities in ICSI conceived male children. However, more studies are needed to clarify these phenomena.
IVF together with ICSI enables many men with serious fertility issues to father children.