INTRA CYTOPLASMIC SPERM INJECTION (ICSI)
Naturally, the fertilisation process involves the penetration of a single sperm from the ejaculate into the egg (called oocyte in scientific terms) released during the menstrual cycle. Said sperm must penetrate the shell of the oocyte (called zona pellucida) to immediately fuse with the female gamete.
Sometimes, either due to physiological deficiencies that may lead to a drastic reduction or absence in the production of gametes or due to poor gamete quality or defects in the interaction, the process of fertilisation can be diminished or even prevented.
From the Assisted Reproduction Techniques (ART) perspective there are two main approaches to overcome these deficiencies:
- Conventional In Vitro fertilisation (IVF)
- Intra Cytoplasmic Sperm Injection (ICSI).
1. Conventional IVF
Conventional IVF is based on the interaction between the oocytes and the sperm. After the egg retrieval, each oocyte and the set of cells that surround it (granulose cells) will be put in a drop of culture media containing a suspension of sperm at a given concentration. From this interaction a single sperm should penetrate into the egg to fertilise it.
2. Intra-Cytoplasmic Sperm Injection (ICSI)
ICSI is based on the insertion of a selected sperm into the oocyte, overcoming the limitations that conventional IVF faces with poor semen samples and deficiencies in the interaction between the gametes. Because of this, ICSI has become the most commonly used IVF technique. With the help of an advanced micromanipulation station (including microscope, microinjectors and micropipettes) the sperm has to be individually selected and immobilised. During the microinjection the oocyte has to be held while the sperm is inserted and released inside the inner part of the oocyte. The day after the microinjection, signs of proper fertilisation will be checked in each oocyte.
Limitations of the technique
Although the technique mimics the natural interaction between the gametes that occur in the fallopian tubes. It requires a certain semen concentration due to which not all samples are capable of being used for conventional IVF.
Likewise, the technique cannot solve the possible problems of interaction between female and male gametes so, the uncertainty about the success of the procedure is generally higher.
Who is this for?
The indications of conventional IVF and ICSI are tubal factor, uterine factor, premature ovarian failure, ovulatory dysfunction, endometriosis, diminished ovarian reserve and unexplained infertility. ICSI is specially recommended for samples presenting alterations in the semen analysis (mostly in cases of low concentration or motility), situations in which there are a limited number of oocytes available or in cases of previous fertilisation failures with conventional IVF. This leads conventional IVF to be usually indicated in good prognosis patients were the quality of both gametes is not an apparent limitation.
IVF was originally developed for women with blocked tubes or missing fallopian tubes and it is still the procedure of choice for these situations. It is also used when other conditions are present, including endometriosis, male factor infertility and unexplained infertility in which no medical cause for infertility can be found. Our experts will review your history and help to guide you to the treatment and diagnostic procedures that are most appropriate for you.
1/3rd of the infertility issues are contributed by the male partner. Male factors also influence increased rate of miscarriages. Most common causes of male infertility are as follows.
- Abnormal sperm count or low sperm motility
- Chronic ailments such as cancer
- Environmental factors: Exposure to radioactive chemicals
- Lifestyle factors: Being overweight, smoking, drinking alcohol
Infertility is gender neutral. It affects the male and the female population. 1/3rd of the infertility issues are contributed by the female partner. In the world 50-80 million suffer from infertility. Most common causes of female infertility are as follows.
- Hormonal issues leading to ovulation problems
- Tubal blockage
- Lifestyle factors: Being overweight, smoking, drinking alcohol, unhealthy diet
- Unexplained infertility
Women are born with approximately 2 million eggs in their ovaries. Before a girl reaches puberty, about 11,000 eggs die every month. Thus, in her teenage years, a woman has only about 300,000 to 400,000 eggs available. From this point onwards, about 1000 eggs are utilised every month. This has nothing to do with any form of birth control, pregnancy, hormone production, health, lifestyle or nutritional supplements. Eventually, a woman reaches menopause when she has no viable eggs left.
PCOS (Polycystic Ovarian Syndrome) refers to a condition caused by hormonal imbalances. Women suffering from PCOS produce higher than normal amounts of male hormones. This affects ovulation and can result in irregular periods. In some cases, women suffering from PCOS may have irregular periods. This, in turn, can make it harder for these women to conceive. In fact, PCOS is one of the most common causes of female infertility.