Sperm sometimes fail to fertilise even when they are artificially placed within reach of eggs during a conventional in vitro fertilisation (IVF) procedure. Fertilisation failure can be an extremely stressful experience for couples undergoing IVF and embryo transfer cycles, as also for clinicians. Fertilisation failure occurs in 3% to 10% of IVF cycles, and 1% to 3% of intracytoplasmic sperm injection (ICSI) cycles. In the absence of fertilisation, an embryo is not created, and consequently, the embryo transfer stage of an IVF cycle is never reached.
Despite the advancement of assisted reproductive technologies and tools, it is hard to gauge the odds of fertilisation failure or subpar fertilisation in patients seeking fertility treatments. The truth is, fertilisation failure isn’t limited to low-quality sperm; it has been known to occur even in cases of natural insemination with normal sperm.
Here’s where ICSI comes in. ICSI is an IVF procedure in which a single sperm is deposited directly into an egg. Defective sperm function is one of the most common causes of male infertility. Up to 15% of severe male infertility cases are attributed to genetic factors, while the remainder are triggered by environmental influences.
Over the past decade, ICSI has been used extensively to treat severe male infertility across the globe. The technique has been pointed at two types of couples: those whose prior IVF cycles have proved unsuccessful, and those who have not been able to qualify for IVF owing to low sperm motility or morphology. ICSI is usually opted for by couples with unexplained infertility, subpar or inadequate oocytes, advanced maternal age, previous fertilisation failure with conventional insemination, and a history of genetic disorders. It is also recommended for couples who would like to thaw, restore and fertilise previously frozen eggs.
The first baby created through ICSI was born in Singapore in April 1989. The technique was originally developed by Gian Piero Palermo at Vrije Universiteit Brussel. He devised the method while working at the Centre for Reproductive Medicine, headed by Paul Deveroy and Andre Van Steirteghem.
ICSI follows a phased approach, and entails the following steps:
*The extraction of sperm from the epididymis is known as percutaneous epidydimal sperm aspiration (PESA). The extraction of sperm from the testicles is known as testicular sperm aspiration (TESA).In ICSI, sperm selection happens based on visual assessment. Physiological Intracytoplasmic Sperm Injection (PICSI) is a more precise sperm selection tool than ICSI, identifying healthy sperm using a collection of medium-based methods. A recent clinical trial showed that embryos derived through PICSI could lower the chances of miscarriage. ICSI has helped countless couples in overcoming infertility over the last 28 years.
Authored By - Dr. Indu Madhusudhan
Cloudnine Fertility - JP Nagar
IVF and ICSI are distinct fertilisation methods that happen in the laboratory. In IVF, eggs and sperm are allowed for natural fertilisation in a laboratory, whereas in ICSI, a single sperm is selected and injected into each egg. ICSI is an advanced IVF technique with a better fertilisation rate than IVF.
ICSI is an effective fertility treatment in cases of male fertility issues. But, there are certain risks associated with the procedure, including congenital disabilities, genetic abnormalities, genetic transmission of fertility issues and neurodevelopmental issues. However, the risks of ICSI are low, making it a safe fertility treatment option.
ICSI is an effective and specialised treatment option compared to IVF for male fertility issues. Fertilisation failure is less in the case of ICSI, i.e., 1% to 3 % compared to IVF, which is 3% to 10%. Also, ICSI is more successful in cases of defective sperm function.
Research suggests that there is a potential impact on the sex ratio of the offspring with ICSI fertility treatment. In this procedure, a single sperm is directly injected into an egg, increasing the chances of female births.
