What Is ICSI in IVF Treatment?
Quick Answer
ICSI (intracytoplasmic sperm injection) is a laboratory technique used during IVF where a single sperm is injected directly into a mature egg to achieve fertilization. It was originally developed for severe male factor infertility but is now widely used across many IVF cycles. ICSI fertilization rates typically reach 70 to 80%.
At Markham Fertility Centre, ICSI is included in all funded IVF cycles at no additional cost and is available for private cycles when clinically indicated.
How ICSI Works
In conventional IVF, thousands of sperm are placed around each egg in a laboratory dish and fertilization is left to occur naturally. With ICSI, the embryologist selects a single healthy sperm and injects it directly into the egg’s cytoplasm using a microscopic needle (micropipette).
The key steps:
- Egg preparation: After retrieval, mature eggs are stripped of surrounding cells to allow the embryologist to assess quality and inject precisely
- Sperm selection: The embryologist evaluates sperm under high magnification, selecting one with the best morphology and motility
- Injection: The selected sperm is immobilized, drawn into a fine glass needle, and injected directly through the egg’s outer shell (zona pellucida) and membrane into the cytoplasm
- Incubation: The injected egg is placed in a controlled incubator and checked the following day for signs of fertilization
- Embryo culture: Fertilized eggs develop into embryos over 3 to 5 days, just as in conventional IVF
The entire injection process takes only seconds per egg. All subsequent steps (embryo culture, transfer, freezing) are identical to conventional IVF.
ICSI vs. Conventional IVF Fertilization
| Factor | Conventional IVF | ICSI |
| How fertilization occurs | Sperm and eggs mixed in a dish; sperm penetrates egg naturally | Single sperm injected directly into the egg |
| Sperm needed per egg | 100,000 | 1 |
| Fertilization rate | 60-80% of mature eggs | 60 to 80% of mature eggs eggs |
| Best suited for | Normal sperm parameters | Male factor infertility, prior fertilization failure |
| Cost | Included in base IVF fee | $1,500 to $2,500 additional at most clinics; included at no additional cost in funded and private cycles at MFC |
When ICSI Is Recommended
Your fertility physician may recommend ICSI when:
- Severe male factor infertility: Very low sperm count (below 2 million per mL), poor motility, or abnormal morphology
- Surgically retrieved sperm: Sperm obtained via TESA, MESA, or testicular biopsy (e.g., after vasectomy, obstructive azoospermia)
- Previous IVF fertilization failure: Prior cycles where conventional fertilization resulted in few or no fertilized eggs
- Low egg yield: When few eggs are retrieved, ICSI maximizes the chance of fertilizing each one
- Frozen eggs: Thawed eggs must use ICSI to facilitate fertilization
- Unexplained infertility: When no clear cause has been identified and the physician wants to optimize fertilization
At some clinics, ICSI is now used as the default fertilization method for all IVF cycles. At MFC, it is recommended on an individual case by case basis and it is included free of extra charge in every funded IVF cycle and private IVF cycles.
Risks and Limitations
ICSI is considered safe and has been used clinically since 1992. However, patients should be aware of:
- Egg damage: A small percentage of eggs (5 to 10%) may be damaged during the injection process and will not survive
- No guarantee of fertilization: Even with direct injection, some eggs may not fertilize (approximately 20 to 30% of injected eggs)
- No guarantee of pregnancy: Fertilization is only one step. Embryo development, implantation, and pregnancy depend on many other factors.
- Slightly increased risk of sex chromosome abnormalities: Some studies suggest a very small increase, though the absolute risk remains low. This is likely related to the underlying male infertility rather than the ICSI technique itself.
- Cost at some clinics: ICSI adds $1,500 to $2,500 per cycle when it is not included in the base fee
ICSI Cost in Ontario
| Scenario | Typical ICSI cost |
| OFP-funded IVF cycle | Included (no additional cost) |
| Private IVF cycle (most clinics) | $1,500 to $2,500 additional |
| Private IVF cycle at MFC | Included when clinically indicated |
For Ontario residents using their funded IVF cycle through the Ontario Fertility Program, ICSI is covered at no extra charge. The Ontario Fertility Treatment Tax Credit (25% of eligible expenses, up to $5,000/year) applies to ICSI costs in private cycles.
Why Patients Choose Markham Fertility Centre for IVF with ICSI
- ICSI included in all funded AND private IVF cycles at no additional cost
- On-site embryology lab with experienced embryologists performing ICSI daily
- Pain-free egg retrieval with an anesthesiologist at every procedure, the only clinic in Ontario to offer this
- On-site genetics program for PGT-A and PGT-M counselling at no additional cost (ICSI is required for PGT)
- Five locations across Markham, Barrie-Innisfil, Oshawa, Orillia, and Sudbury for monitoring
- Transparent pricing with clear breakdowns of what is and is not included
Learn more about IVF at Markham Fertility Centre →
FAQ
Is ICSI better than conventional IVF?
ICSI is not inherently better. It achieves higher fertilization rates and is essential for severe male factor infertility, but pregnancy and live birth rates are comparable when fertilization is successful with either method. Your physician will recommend ICSI when it offers a clear clinical benefit.
Does ICSI hurt?
No. ICSI is a laboratory procedure performed on eggs after retrieval. The patient is not involved in or aware of the ICSI process. The only physical step the patient experiences is the egg retrieval itself.
Is ICSI safe for the baby?
Yes. Over 30 years of clinical data show no significant differences in health or development between children conceived through ICSI and those conceived naturally. The slightly elevated risk of certain chromosomal issues is attributed to the underlying infertility, not the technique.
Can ICSI be used with frozen eggs?
Yes. ICSI is the standard fertilization method for frozen (vitrified) eggs because the freezing process hardens the outer shell, making natural sperm penetration unlikely.
Does ICSI increase the chance of twins?
No. ICSI does not increase the risk of multiple pregnancy. The number of embryos transferred determines the risk of twins, not the fertilization method. Single embryo transfer (eSET) is now standard practice at most clinics to minimize this risk.