ICSI (Intracytoplasmic Sperm Injection) is an Assisted Reproductive Technique. It is very similar to conventional IVF (In Vitro Fertilisation) and is used with IVF. The only difference between IVF and ICSI is the method of achieving fertilisation.
ICSI is a laboratory procedure and is used in case of male factor infertility. This technique provides an option for infertile males to grow family without the need of a donor sperm.
In IVF treatment egg and sperm collected from both the partners are mixed in a dish where Sperm itself fertilises the egg naturally. In conventional IVF large number of actively swimming sperms are required to increase the chance of fertilisation.
In some cases sperm availability is limited or the sperm is unable to fertilise an egg naturally in such cases ICSI is used. In this method, sperm is injected into the egg to fertilise the egg and after fertilisation all the other process are similar to that in IVF.
Some fertility treatment clinics recommend ICSI to couples with severe male factor infertility while some follow this to every IVF cycle.
ICSI is used in the following conditions:
Azoospermia: It is a condition in which semen lacks sperm. There is no viable sperm found in the ejaculated fluid. In such cases, sperm is extracted from testes or epididymis. Extracted sperms are then used to fertilise egg via ICSI technique.
Oligospermia: In this condition, there is less number of sperms in semen. If the sperm count is less than 15 million per ml then Less number of sperm decreases the chance of fertilisation in that case ICSI technique is used to fertilise the egg.
Low Sperm Motility: When sperm is immobile, it cannot penetrate the egg because it needs to move in order to reach the egg wall. In such cases, a single sperm is picked up and injected into the egg.
Poor Sperm Morphology: Morphologically abnormal sperms like round-headed sperms (globozoospermia) are unable to penetrate the egg. These kind of sperms can fertilise egg only by ICSI.
Vasectomy: It is a surgical method of permanent conception. In this surgery, vas deferens is cut and tied so that sperm cannot travel to the urethra and hence cannot fertilise an egg.
ICSI-IVF treatment can help a person to have kids after vasectomy even without having a vasectomy reversal. Sperms are extracted directly from testes or epididymis and are injected into the egg by the use of ICSI technique only.
Difficulty In Ejaculation: When a person is having a problem with ejaculation such as retrograde ejaculation in that case only way to get the sperm to reach the egg is through ICSI Technique.
Retrograde ejaculation is a condition in which sperm enter into the urinary bladder and little or no sperm is present in the ejaculated semen.
Cryopreserved Sperm: When sperm sample preserved before chemotherapy or radiotherapy is used for fertilisation, in such cases frozen sperm sample is very valuable because it is present in limited quantity. In such cases to avoid the risk of treatment failure, ICSI-IVF is used.
Frozen Egg: Eggs are preserved by vitrification technology and it sometimes hardens the eggshell and makes it impossible for sperm to fertilise an egg naturally. In such cases, sperm is injected into the egg by ICSI.
Recurrent IVF Failure: In cases where conventional IVF treatment is getting failed even after several IVF cycles. There could be many possible reasons for recurrent IVF failure. In such cases ICSI is used along with IVF. Its success rate is higher than conventional IVF.
Infertility Due To Immune Factor: When antisperm antibodies are present in cervicovaginal secretion or serum, ICSI-IVF is required for fertilisation. Antibodies present in vaginal secretion fights against sperm and hence, do not allow fertilisation.
ICSI is a method of achieving fertilisation to develop embryo for In Vitro Fertilisation. It is performed in a laboratory hence, it is not much different from IVF for the patient. Except for the process of fertilisation, all the steps are the same as IVF.
Step by step process of ICSI-IVF is as follows:
Step 1: Stimulation Of Ovaries
Normally every woman produces one egg per month but for IVF procedure more eggs are required to produce a large number of the embryo. This is done to increase the success rate of the procedure.
To achieve this, ovulation is boosted through some drugs via daily injections. These drugs cause the ovaries to produce more oocytes so that at the time of retrieval ovaries contain more eggs.
Step 2: Egg retrieval
Doctors decide the time of egg retrieval after hormone testing and ultrasound.
When there are enough mature eggs present in ovaries, eggs are retrieved from ovaries to fertilise them with sperm.
Egg retrieval takes place using an ultrasound-guided needle. Fluid from ovaries is carefully withdrawn and examined for the presence of eggs.
This process is done under sedation so that the patient do not feel any pain or discomfort.
Step 3: Sperm Collection
On the same day when the egg is retrieved from the female partner, the sperm sample is collected from the male partner. Unless cryopreserved or frozen sperm is being used.
Step 4: ICSI (Intracytoplasmic Sperm Injection)
After the collection of egg and sperm, sperm with the best morphology and mobility is selected. This selected sperm is then microinjected into the oocyte.
In this process, a single sperm is placed into a tiny pipette and is carefully injected into the egg.
The embryos obtained by this fertilisation are then allowed to grow in the laboratory for 3 to 5 days.
Step 5: Transfer Of Embryo
Not all embryos may remain viable, some may get blocked in development. The best embryos are selected for transfer into uterus according to their morphology and development.
Best embryos that are grown in these 3-5 days are then transferred into the uterus of the female for implantation.
In some cases, where the uterus of the intended mother is not suitable for implantation and embryo is transferred to another woman (surrogate) to carry the pregnancy to due term and give birth to the child, is known as surrogacy.
In some cases, excess embryos may develop in the uterus after transfer. And this leads to multiple pregnancies.
ICSI can increase the success rate of IVF but this is associated with some risks which are as follows:
This process involves injecting the egg and stripping cells around it that’s why Some eggs and embryos are damaged during the ICSI procedure.
ICSI allows less healthy sperm to fertilise an egg and hence it may result in defective embryo.
Sometimes in ICSI-IVF egg fails to fertilise normally or stop growing at an early stage of development.
Chances of multiple pregnancies are higher in couples conceiving with ICSI-IVF as compared to conventional IVF. Multiple pregnancies may cause other complications like premature delivery, low birth weight, anemia, birth defect miscarriage etc.
ICSI has a slightly higher risk of birth defects as compared to normal pregnancy.
In the male child born by ICSI process, there are more chances of having fertility problems in future as Infertility might get passed on genetically.