Updated: Oct 21, 2021
Intracytoplasmic sperm injection is an in vitro fertilization (IVF) procedure in which a single sperm cell is injected directly into the cytoplasm of an egg. 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.
There are several differences within classic IVF and ICSI. However, the steps to be followed before and after insemination are the same.
In terms of insemination, ICSI needs only one sperm cell per oocyte, meanwhile IVF needs 50,000 - 100,000. This is because the acrosome reaction has to take place and thousands of sperm cells have to be involved in IVF.
Once fertilized, the egg is transformed into a pro-embryo and it has to be transferred to the uterus to continue its development.
How Is ICSI Performed?
ICSI involves five basic steps, outlined below.
Step 1. Sperm Collection
First, a semen sample is retrieved from the male partner. This semen may be organically collected or acquired via a surgical testicular procedure.
Step 2. Egg Collection
Once a semen sample has been collected, a selection of mature eggs is surgically extracted from the female partner.
Step 3. Sperm Injection
Next, a single sperm cell is injected into a healthy egg using a hollow needle.
Step 4. Observation
Once the egg is fertilised, it becomes an embryo and is cultured in a laboratory for approximately four to five days.
Step 5. Implantation
Once an embryo is about four or five days old, it is transferred to the uterus. A few days later, it embeds itself into the uterine lining, a process known as implantation.
Is ICSI Painful?
ICSI treatment is ideal for men with a low sperm count, or poor sperm motility or morphology. The process hinges on adequate sperm collection, which may be done organically or with surgical intervention. Usually, sperm is collected via normal ejaculation. For men who have undergone a prior vasectomy, a microsurgical vasectomy reversal may first be required for restoring fertility.
And then, there's needle aspiration
Needle aspiration or microsurgical sperm retrieval may be recommended when a microsurgical vasectomy reversal does not reap the required results in fertility restoration. The procedure allows a fertility specialist to obtain sperm from the testicles using a fine needle. Although needle aspiration is a straightforward procedure performed under anaesthesia, it does present a slight risk of pain and swelling. In most cases, it results in minimal discomfort.
Will ICSI work?
ICSI fertilizes 50% to 80% of eggs. But the following problems may occur during or after the ICSI process:
Some or all of the eggs may be damaged.
The egg might not grow into an embryo even after it is injected with sperm.
The embryo may stop growing.