What is ICSI Treatment? Everything You Need to Know

What is ICSI Treatment? Everything You Need to Know

Intracytoplasmic Sperm Injection (ICSI) has become an important part of modern fertility care, especially when male factor infertility stands in the way of natural conception. 

ICSI overcomes many obstacles that sperm face in traditional in vitro fertilization (IVF) by directly injecting a single healthy sperm into an egg’s cytoplasm. Couples who have struggled with low sperm counts, poor motility, or repeated failed IVF cycles now find real hope through this precise technique. 

In this comprehensive guide, we will cover every aspect of ICSI treatment from what the acronym stands for to detailed steps of the procedure, costs in India, a comparison with other ART methods, success rates, potential risks, and post-treatment care. 

What Is ICSI? Full Form and Definition 

ICSI stands for Intracytoplasmic Sperm Injection. In traditional IVF, hundreds or thousands of sperm surround an egg in a laboratory dish, hoping one will penetrate naturally. With ICSI, that uncertainty disappears. A highly skilled embryologist uses a fine glass needle to immobilize and pick up one motile sperm. 

Under a powerful microscope, the technician then penetrates the egg’s outer layer (zona pellucida) and deposits the sperm into its cytoplasm. This direct approach bypasses many of the barriers sperm face, such as poor motility or abnormal shape, and greatly increases the chances of fertilization when male infertility is severe.

How ICSI Differs from Other Assisted Reproductive Technologies 

Assisted Reproductive Technology (ART) includes several techniques that help couples conceive when natural methods fail. The most common are Intrauterine Insemination (IUI), Conventional IVF, and ICSI. They all work toward the same goal: fertilization and embryo transfer, their approaches differ significantly.

Intrauterine Insemination (IUI)

Sperm are washed and concentrated, then placed directly into the uterus around the time of ovulation. Couples with mild male factor infertility, unexplained infertility, or cervical mucus issues.

• Success Rate: Approximately 10–20% per cycle.
• Advantages: Least invasive, lowest cost, minimal medications.
• Limitations: Relies on sperm swimming through the reproductive tract to reach the egg.

Conventional In Vitro Fertilization (IVF)

Eggs are retrieved and mixed with thousands of sperm in a lab dish. Fertilization happens if one sperm penetrates the egg naturally. Various infertility factors, including female tubal issues, endometriosis, or moderate male factor.

• Success Rate: 40–50% per cycle for women under 35.
• Advantages: Well-established, can create multiple embryos in one cycle.
• Limitations: Requires decent sperm count and motility; fertilization is not guaranteed.

Intracytoplasmic Sperm Injection (ICSI)

A single sperm is injected directly into each mature egg’s cytoplasm. Severe male factor infertility (low count, poor motility, abnormal morphology), previous failed IVF, use of frozen or surgically retrieved sperm.

• Success Rate: Comparable to conventional IVF when egg quality is equal; fertilization rates of 50–80%.
• Advantages: Bypasses natural barriers; high fertilization rates even with few or poor-quality sperm.
• Limitations: More complex, higher cost, requires specialist equipment and skills.

Who Needs ICSI Treatment?

ICSI is a powerful tool when male fertility issues limit conventional IVF success. Your fertility specialist may recommend ICSI if you or your partner experience any of the following:

Low Sperm Count (Oligospermia)

When few sperm are present, chances of one reaching and fertilizing the egg naturally or in an IVF dish drop significantly.

Poor Sperm Motility (Asthenozoospermia)

If sperm cannot swim effectively, they cannot penetrate the egg’s outer shell on their own. ICSI bypasses this hurdle.

Abnormal Sperm Shape (Teratozoospermia)

Irregular head or tail shapes can impair a sperm’s ability to bind and fuse with an egg. Direct injection avoids that requirement.

Azoospermia with Surgical Retrieval

In cases where no sperm appear in the ejaculate (azoospermia), sperm can be extracted from the testicle (TESE) or epididymis (PESA). Even small numbers of sperm retrieved this way can be used for ICSI.

Retrograde Ejaculation

When sperm travel backward into the bladder, ICSI makes use of whatever viable sperm can be collected.

Failed Fertilization in Previous IVF Cycles

If no eggs are fertilized in standard IVF, switching to ICSI often achieves fertilization.

Use of Frozen or Donor Gametes

Thawed sperm or eggs may have reduced vigor. ICSI maximizes the likelihood that a viable sperm will fertilize each mature egg.

Even when male parameters appear normal, couples with unexplained infertility or repeated IVF failures may choose ICSI to improve fertilization odds. A thorough evaluation by a reproductive endocrinologist will determine whether ICSI is the best path.

ICSI Treatment Procedure: Step by Step 

1. Ovarian Stimulation and Monitoring
During the first phase of ICSI treatment, you receive daily injections of follicle-stimulating hormone (FSH) and, in some protocols, luteinizing hormone (LH) analogs for about 8 to 14 days. Your doctor selects a “long,” “short,” or GnRH-antagonist regimen based on your age, ovarian reserve, and prior responses to stimulation. 

Every two to three days, you undergo a transvaginal ultrasound to measure the size of the developing follicles and the thickness of your uterine lining. At the same time, blood tests check estradiol levels to ensure that the growing follicles are producing the expected hormones. 

Once the leading follicles reach approximately 18–20 mm in diameter, you receive a “trigger” injection of hCG or a GnRH agonist. This final shot prompts the eggs to complete maturation, and precisely 34–36 hours later egg retrieval is scheduled to collect the mature oocytes at their optimal development stage.

2. Egg Retrieval (Oocyte Collection)
Egg retrieval is done using transvaginal ultrasound guidance, your physician inserts a thin needle through the vaginal wall into each ovarian follicle. Gentle suction draws the follicular fluid, which contains the eggs, into sterile test tubes. 

The process typically lasts 10–20 minutes, and most patients go home the same day. Mild cramping or spotting afterward is common, and you’ll receive post-procedure instructions for rest, pain management, and signs to watch for, such as excessive bleeding or fever.

3. Sperm Collection and Preparation
On the morning of egg retrieval, your partner provides a semen sample following two to three days of sexual abstinence. In the laboratory, technicians process the sample using density-gradient centrifugation or swim-up techniques to isolate the most motile, healthy sperm. 

If no sperm are present in the ejaculate (azoospermia) or the sample cannot be produced, surgical methods such as testicular sperm extraction (TESE) or percutaneous epididymal sperm aspiration (PESA) are employed to retrieve sperm directly from the testes or epididymis. Retrieved sperm can be used fresh or cryopreserved for future cycles.

4. Micromanipulation and Sperm Injection
In a specialized embryology lab, a skilled embryologist uses an inverted microscope fitted with micromanipulators. One pipette holds each mature egg in place, while an injection pipette immobilizes and draws up a single sperm often by gently breaking its tail to improve handling. 

The embryologist then carefully penetrates the egg’s outer shell (zona pellucida) and membrane (oolemma) to deposit the sperm directly into the cytoplasm. This precise technique bypasses natural barriers to fertilization and is completed for each egg under strict temperature and pH-controlled conditions.

5. Post-Injection Culture and Fertilization Check
After injection, the eggs are transferred into individual microdrops of culture media under oil and incubated at 37 °C with 5–6% CO₂. Approximately 16–18 hours later, embryologists examine each egg for evidence of normal fertilization marked by the presence of two pronuclei. 

Unfertilized or abnormally fertilized eggs are discarded. Successfully fertilized zygotes are then monitored as they divide: by day 2–3 they reach the cleavage stage (4–8 cells), and by day 5–6 they form blastocysts, with an inner cell mass destined to become the fetus and an outer trophectoderm that will form the placenta.

6. Embryo Grading and Selection
Each developing embryo is graded based on cell number, symmetry, and the extent of fragmentation. High-quality blastocysts are preferred for transfer or cryopreservation. Grading helps predict which embryos have the best chance of implanting and developing into a healthy pregnancy. 

Embryologists and your physician review these grades together to determine the optimal number and stage of embryos to transfer, balancing the desire for success with the risks of multiple pregnancy.

7. Embryo Transfer and Luteal Support
On day 3 (cleavage stage) or day 5 (blastocyst stage), the selected embryo(s) are loaded into a thin catheter and placed into the uterine cavity under ultrasound guidance. This quick procedure causes minimal discomfort. 

After transfer, you begin progesterone support delivered via injections, vaginal gels, or suppositories to prepare and maintain the uterine lining for implantation. Progesterone continues until around 10–12 weeks of gestation, when the placenta takes over hormone production.

8. Pregnancy Testing and Early Follow-Up
Approximately 10–14 days after embryo transfer, a blood test measures β-hCG to confirm pregnancy. A rising hCG level suggests successful implantation. If positive, an ultrasound at 6–7 weeks checks for a gestational sac and fetal heartbeat.

Throughout early pregnancy, your team monitors hormone levels, ultrasounds, and overall well-being, addressing any complications promptly to support a smooth transition into the second trimester.

ICSI Treatment Cost in India (INR)

ICSI involves specialized laboratory equipment, embryologist expertise, and additional steps compared to standard IVF. As a result, it carries higher fees. The data below outlines typical costs in Indian rupees (INR). Prices can vary by clinic, city, and patient-specific protocols.

Total per ICSI Cycle: ₹150,000–₹250,000

Additional Costs to Consider

• Genetic Testing (PGT-A/PGT-M): ₹50,000–₹100,000 extra
• Cryopreservation: ₹5,000–₹15,000 per year
• Surgical Sperm Retrieval (TESE/PESA): ₹30,000–₹60,000

Benefits of ICSI Treatment

ICSI treatments can have several benefits to overcome infertility, they are as follows:

• ICSI enables fertilization even when sperm count is extremely low or motility is poor. Single sperm injection bypasses natural barriers.
• Embryologists achieve fertilization rates of 50–80% per injected egg by placing sperm directly into the egg
• Men with no sperm in their ejaculate can still father biological children using sperm extracted directly from the testes or epididymis.
• Couples who had no fertilization in standard IVF cycles often succeed with ICSI the next time.
• ICSI is effective using thawed sperm and/or eggs, aiding fertility preservation plans.
• Because each egg is directly injected, the chance of zero fertilized eggs is minimized.
• Multiple embryos can be created in one cycle, allowing for fresh transfers or cryopreservation for future attempts.

Risks and Limitations of ICSI 

Although ICSI is a safe alternative, it may have some risks associated with it but they are not that common:

• The microinjection needle may damage the egg membrane or internal structures, leading to egg degeneration in some cases.
• Even with direct injection, not all eggs will fertilize. Factors like egg quality and technique precision matter.
• Some embryos may stop dividing or develop abnormally despite successful fertilization (Embryo Arrest)
• ICSI requires specialized micromanipulation equipment and highly trained embryologists, increasing the financial and logistical burden.
• Slightly higher rates of certain congenital or imprinting disorders (e.g., Angelman syndrome, Beckwith-Wiedemann syndrome) have been reported, possibly reflecting underlying male factor issues rather than the procedure itself.
• The technical nature of ICSI may cause additional stress for couples. Counseling and support services are crucial.

Success Rates and Factors Influencing Outcomes 

Key Influencers of ICSI Success are as follows: 

• Woman’s Age: Younger women produce eggs with better developmental potential.
• Egg Quality: Eggs with good maturity and minimal chromosomal abnormalities yield stronger embryos.
• Sperm DNA Integrity: Even with ICSI, severely fragmented DNA may reduce embryo viability.
• Embryo Grading: Higher-graded embryos are more likely to implant and develop.
• Uterine Receptivity: A healthy endometrial lining with optimal thickness (8–12 mm) and blood flow supports implantation.
• Clinic and Lab Expertise: Success rates correlate strongly with the skills of the medical and laboratory teams.

Typical Success Rates

Success declines with maternal age, particularly after age 38. Couples should review clinic-specific rates and ask about outcomes in patients with similar diagnoses.

Fertilization Rate: 50–80% of injected eggs fertilize.

Clinical Pregnancy Rate: 40–50% per transfer for women under 35.

Live Birth Rate: 35–45% per cycle, depending on age and clinic.

When to Call for Help

Contact your doctor or clinic immediately if you experience:

• Severe abdominal pain or heavy bleeding
• Fever, chills, or signs of infection
• Sudden dizziness or fainting (possible ovarian hyperstimulation syndrome)
• Symptoms of ectopic pregnancy (sharp one-sided pain)
• Early intervention can manage complications and safeguard your health.

Conclusion 

Intracytoplasmic Sperm Injection (ICSI) stands as a ray of hope for couples facing severe male infertility or repeated failed fertilization. By directly introducing a single healthy sperm into an egg’s cytoplasm, ICSI overcomes natural barriers and delivers fertilization rates far beyond what traditional IVF can achieve under challenging conditions. 

Though the procedure involves higher costs, specialized equipment, and the expertise of a trained embryology team, its benefits particularly for those with low sperm counts, poor motility, or surgically retrieved sperm are profound.

Success with ICSI depends on multiple factors: maternal age, egg and sperm quality, embryo development, and uterine receptivity. Couples who choose ICSI should gather detailed information on clinic success rates, financial implications, and post-procedure care. 

With appropriate medical guidance, lifestyle support, and emotional counseling, many couples achieve pregnancy and take the first steps toward parenthood.