Intra-Cytoplasmic Sperm Injection (ICSI) has probably been the most significant development in IVF since it began in 1992. The advantage of ICSI is that as long as some sperm can be obtained (even in low numbers), a man can be a biological father. The technique has revolutionised male factor infertility and often removed the need for donor sperm, the only previous option for couples.
The procedure involves the injection of a single sperm directly into an egg to fertilise it. The fertilised egg is then incubated and transferred to the woman’s womb in the same way as in other IVF procedures. The success rates with ICSI are very similar to general IVF rates, and results are generally shown together.
ICSI is recommended when
- The man has a very low sperm count or no sperm in the samples
- Semen samples have many abnormal sperm or poor motility
- The man’s sperm are unable to fertilise an egg (additional semen tests)
- Previous IVF cycles had either unexpectedly low fertilisation rates or failure
- A vasectomy requires the surgical collection of sperm from the testes or the epididymis (male reproductive organs)
- The man has erectile or ejaculation problems from spinal cord injuries, diabetes or other cause
Procedure
- An embryologist will examine the sperm to decide if ICSI is appropriate
- The preferred option is collecting a fresh semen sample on “Egg Collection” day
- If this isn’t possible, surgical procedures can retrieve sperm from the epididymis or testicles. The options are:
- Percutaneous epididymal sperm aspiration (PESA)
- Testicular sperm aspiration (TESA)
- Testicular sperm extraction (TESE)
- Each egg is injected with a sperm, which doesn’t guarantee fertilisation, but it does bypass many potential barriers to conception
- Between one and three of the best quality embryos will be transferred later
Risks
Because ICSI is a relatively recent treatment, the possible long-term consequences for the child aren’t entirely known, but the risks associated with ICSI so far are:
- Certain genetic and developmental defects may be due to underlying issues that required ICSI rather than the technique itself
- It’s possible that boys conceived using ICSI may inherit a father’s infertility, and the initial findings of boys conceived with ICSI support this. ICSI offspring have half the sperm count, motility and concentration of typically conceived young men
- There’s a higher risk of miscarriage, probably as the technique uses sperm that possibly wouldn’t otherwise have been able to fertilise an egg
- A low sperm count could be passed to a male child, which makes genetic testing before choosing ICSI for cystic fibrosis genes and other chromosome abnormalities a consideration. Discussing the full implications of testing with the embryologist or a specialist counsellor is recommended before testing
