What is Intracytoplasmic Sperm Injection (ICSI)?
Intracytoplasmic sperm injection (ICSI) involves the direct injection of sperm into eggs obtained from in vitro fertilization (IVF).
Are there specific situations where ICSI might be recommended?
ICSI may be recommended when there is a reason to suspect that fertilization may be difficult because of male infertility factors. Male infertility factors can include any of the following problems: low sperm count, poor motility or movement of the sperm, poor sperm quality, or sperm that lack the ability to penetrate an egg.
Azoospermia is a condition where there is no sperm in the males ejaculation. There are two types of azoospermia, obstructive and non-obstructive. Obstructive azoospermia may be caused vasectomy, an absence of vas or from scarring from prior infections. Non-obstructive azoospermia occurs when the testes are not producing sperm.
How is ICSI performed?
There are five steps to ICSI:
The mature egg is held with a specialized pipette.
A very delicate hollow needle is used to pick up a single sperm.
The needle is carefully inserted through the outer membrane of the egg and into the cytoplasm.
The sperm is injected into the cytoplasm, and the needle carefully removed.
How is sperm retrieved for use in ICSI?
For men with low sperm count or sperm with low mobility, normal ejaculation will be used. If the man had a vasectomy, a microsurgical vasectomy reversal is the most cost-effective first option. Needle aspiration or microsurgical sperm retrieval used when a vasectomy reversal fails or when the man is opposed to surgery.
Needle aspiration allows physicians to easily and quickly obtain adequate numbers of sperm for the ICSI procedure. A tiny needle is used to extract sperm directly from the testis. Needle aspiration is performed under sedation with minimal discomfort; however there is potential pain and swelling afterwards.
What health concerns are there when considering ICSI?
Babies from pregnancies through artificial insemination and particularly ICSI have an increased risk for imprinting defects. Genetic imprinting refers to the phenomenon by which particular genes function differently depending on whether the chromosome is inherited solely from the father or from the mother. Prader-Willi Syndrome is an imprinting defect passed on by the father characterized by hypotonia or obesity. Angelman Syndrome is an imprinting defect passed on by the mother characterized by epilepsy or tremors.
Reproductive researchers are increasingly concerned that manipulation of either gametes or zygotes may affect the imprinting process. Additionally, in cases of severe male infertility problems, the genetic cause of the man's infertility may be passed on to the offspring.
