What is ICSI – IVF?
An Intracytoplasmic Sperm Injection is an advanced reproductive procedure wherein a single sperm is directly injected into the egg to cause fertilization. This is accomplished in an embryology lab and is one of two fertilization methods that can be used during IVF. The sperm to be injected is selected using sperm morphology and its forward movement. Aspirated from the sperm-drop into an ICSI needle and then injected into an egg.
ICSI Procedure
Firstly, in an ICSI procedure, doctors identify the best sperm to be directly injected into the egg for fertilization. This is based on sperm morphology and its movement. Aspirated from a sperm-drop the individual sperm is loaded onto a microtool to be injected into the egg. The egg that is to be injected exerts a light suction allowing the embryologist to place it in the right position for the injection.
The embryologist then presses the ICSI needle gently into the side of the egg below the polar body. This punctures the zona pellucida and oolemma, aspirating a small part of the ooplasm into the needle. This is gently mixed before the sperm is placed into the egg. In most cases, embryologists combine several pairs of egg and sperm depending on the number of eggs retrieved during that cycle.
ICSI vs. IVF: What’s the difference between ICSI and Conventional IVF Fertilization?
ICSI is a type of In Virto Fertilization, just as conventional IVF is a different type. While IVF allows for the redressal of severe male factor infertility or females who have significantly blocked fallopian tubes or ovarian conditions, ICSI is a further enhancement of the same process with the advent of technology that allows for embryologists to identify a single sperm that may be best for fertilization.
In the case of conventional IVF, several sperm are used in the hopes that one of them will enter and fertilize the egg on its own. However, ICSI allows the embryologist to take a single sperm and injects it directly into an egg. Advancing technology and benefits associated with ICSI means that it is now widely used in fertility clinics and is typically the method of choice even in cases where male infertility isn’t a factor.
ICSI has a higher fertilization rate of around 50-80% of the eggs being fertilized while in conventional IVF, it is around 50%. ICSI has the possibility to achieve good reproductive outcomes wherein it may have been difficult with conventional IVF.
Why Choose ICSI?
In the case of male factor fertility, ICSI is a perfect solution that gives a much higher possibility of positive fertilization and reproductive rate. With the help of direct sperm injection, the inadequacies of sperm count, motility, and morphology can be overcome which otherwise play a vital role in
fertilization. ICSI gives much higher odds of fertilization and in addition to male-factor fertility also provides a solution for those who underwent a vasectomy and would like to have children or those suffering from paralysis.
ICSI is also a viable path to pregnancy if previous cycles of IVF produced no or very few fertilized eggs if there had been challenges with frozen sperm, challenges associated with fertilization in case of frozen eggs, and of course to have higher odds of fertilization overall.
Does ICSI Guarantee Fertilization?
While ICSI does guarantee a higher possibility of fertilization, it certainly doesn’t guarantee it so. Just like any other fertility procedure, there are chances of failure, however slim they might be. There are various other factors such as maternal age, egg quality, and sperm quality – all of which are pertinent factors to fertilization.
Some of the other reasons for failure could include – poor survival of the egg following the injection, failure to unlock the sperm DNA if there is a lack of de-condensation, and failure of the egg to get activated.
Is ICSI Safe?
Yes, ICSI is a perfectly safe procedure and the risks associated with it remain just as a normal IVF procedure. In fact, ICSI reduces the risk of certain disorders commonly associated with natural birth or other forms of IVF treatment which have been completely eliminated with the use of ICSI.
