Naturally, the fertilization process involves a single sperm from the ejaculate penetrating into the egg (scientifically referred to as an oocyte) released during the menstrual cycle. To merge with the female gamete, the sperm must penetrate the oocyte’s shell (called zona pellucida).
The process of fertilization can be hampered or even blocked in some cases, either due to physiological inadequacies that cause a significant reduction or absence in gamete production or due to poor gamete quality of interaction problems.
There are two basic techniques to solve these shortcomings in Assisted Reproduction Techniques (ART):
1. In Vitro Fertilization (IVF) as it is now practiced (IVF)
2. Injection of sperm into the cytoplasm (ICSI).
ICSI relies on the injection of a single sperm into the egg to overcome the constraints of traditional IVF, such as inadequate semen samples and insufficient gamete interaction. As a result, ICSI has become the most used IVF procedure. The sperm must be individually picked and immobilised using an advanced micromanipulation station (which includes a microscope, microinjectors, and micropipettes). The oocyte must be retained while the sperm is introduced and released inside the inner region of the oocyte during the microinjection. The day after the microinjection, each oocyte will be examined for signs of normal fertilisation.
The method was followed. The interaction between the oocytes and the sperm is the foundation of traditional IVF. Following egg retrieval, each oocyte and its surrounding cells (granulose cells) will be placed in a drop of culture fluid containing a sperm suspension at a specific concentration. A single sperm should reach the egg and fertilize it as a result of this encounter.
Although the approach closely resembles the natural interplay of gametes in the fallopian tubes. Because it necessitates a certain level of semen concentration, not all samples are suitable for traditional IVF. Similarly, because the approach cannot handle potential problems of interaction between female and male gametes, there is a greater degree of uncertainty about the procedure’s success.
Tubal factor, uterine factor, premature ovarian failure, ovulatory dysfunction, endometriosis, decreased ovarian reserve, and unexplained infertility are all indications for traditional IVF and ICSI. ICSI is especially advised for samples with abnormal semen analysis (most commonly low concentration or motility), instances where there are a restricted number of oocytes accessible, or previous fertilisation failures with traditional IVF. As a result, conventional IVF is usually recommended in patients with a good prognosis when the quality of both gametes is not an issue.
