ICSI (Intracytoplasmic sperm injection)

Intracytoplasmic Sperm Injection (ICSI) is an advanced fertility treatment used in cases of male infertility, where traditional in vitro fertilization (IVF) may not be effective. ICSI involves directly injecting a single sperm into an egg to facilitate fertilization. This method is often used when there are issues with sperm quality, quantity, or motility that make natural fertilization difficult.

What Is ICSI?

ICSI is a highly specialized form of IVF, where instead of allowing sperm to naturally fertilize an egg in a lab dish, a sperm is directly injected into the egg using a fine needle. This is done under a microscope, and only one healthy sperm is selected to be injected into the egg. The resulting embryos are then monitored, and the best one is transferred into the woman’s uterus for implantation.

Why Is ICSI Performed?

ICSI is primarily used when there are issues with male infertility, such as:

• Low Sperm Count (Oligozoospermia): When the number of sperm in the semen is too low for natural fertilization to occur.
• Poor Sperm Motility (Asthenozoospermia): When sperm have difficulty swimming or moving towards the egg.
• Sperm Morphology Issues: When sperm have abnormal shapes, affecting their ability to fertilize the egg.
• Azoospermia: A condition where no sperm is present in the semen, which may require sperm retrieval directly from the testes or epididymis.
• Previous IVF Failures: When prior IVF cycles have failed due to sperm quality or fertilization issues.
• Male Genetic Conditions: ICSI can help bypass certain genetic issues that affect sperm function.

How Does ICSI Work?

The ICSI process follows these main steps:

1. Ovarian Stimulation (for the woman):

   • The woman undergoes ovarian stimulation using hormones to produce multiple eggs (oocytes). This is monitored through blood tests and ultrasounds.

2. Egg Retrieval:

   • When the eggs are mature, they are retrieved through a minor surgical procedure called aspiration, where a needle is inserted through the vaginal wall to collect the eggs from the ovaries.

3. Sperm Collection:

   • A sperm sample is collected from the male partner, or if necessary, sperm may be retrieved surgically from the testes or epididymis.
   • The sperm is then processed in the lab to select the healthiest and most motile sperm.

4. Sperm Injection:

   • Under a microscope, a single sperm is carefully injected directly into the cytoplasm of each mature egg using a fine needle. This requires precision and skill from the embryologist.

5. Fertilization and Embryo Culture:

   • After injection, the fertilized eggs (embryos) are cultured in the lab for 2–5 days, during which time they develop and grow.

6. Embryo Transfer:

   • The best quality embryo(s) are selected and transferred into the woman’s uterus, where they may implant and develop into a pregnancy.
   • Excess embryos, if any, can be frozen for future use.

7. Pregnancy Test:

   • About 10–14 days after embryo transfer, a blood test is performed to check for pregnancy (measuring Beta-hCG levels).

Success Rates of ICSI

ICSI has high success rates, particularly for couples with male infertility issues. Success rates can vary depending on various factors, such as the woman’s age, egg quality, and the underlying cause of infertility. On average, ICSI success rates are similar to standard IVF rates, with pregnancy rates ranging from 30% to 50% per cycle, depending on individual circumstances.

• Success rates tend to decrease as the woman’s age increases, particularly after 35.
• ICSI success can also be impacted by the sperm quality and the reason for male infertility.

Benefits of ICSI

• Overcomes Severe Male Infertility: ICSI is particularly helpful for men with low sperm count, poor motility, or other sperm abnormalities.
• Improved Fertilization Rate: Since a single sperm is injected directly into the egg, the chances of fertilization are higher compared to traditional IVF in cases of male infertility.
• Bypasses Sperm Issues: It can bypass problems like low sperm motility or morphology issues that might otherwise prevent fertilization.
• Suitable for Various Male Conditions: It is useful for men with azoospermia (absence of sperm in the semen), who can still have sperm retrieved directly from the testes or epididymis for injection.

Considerations and Risks of ICSI

• Possible Genetic Transmission: Because the sperm is directly injected into the egg, there may be a risk of passing on certain male infertility factors to the child, particularly if the cause is genetic. Genetic counseling may be recommended.
• Multiple Pregnancies: As with other fertility treatments, there is a higher chance of twins or multiple pregnancies, especially when more than one embryo is transferred.
• Egg and Embryo Health: The health of the eggs and embryos may be impacted by the process, although advancements in the procedure have reduced risks.
• Invasive Nature of Sperm Retrieval: In cases of azoospermia, sperm retrieval from the testes or epididymis may be required, which is a surgical procedure that carries its own risks.

Conclusion

Intracytoplasmic Sperm Injection (ICSI) is a breakthrough fertility treatment that offers hope to couples facing male infertility issues. By directly injecting sperm into an egg, ICSI overcomes many of the challenges posed by male reproductive factors, significantly improving the chances of successful fertilization and pregnancy. However, like any fertility treatment, it requires careful consideration of the couple’s unique situation, including the cause of infertility, age, and overall health.