ICSI and SUZIThis IVF technique called intracytoplasmic sperm injection (ICSI) allows a single sperm to be injected directly into the centre of the egg. An alternative is sub-zonal insemination (SUZI), where a single sperm is placed just beneath the zona pellucida (the protein shell which surrounds the egg). ICSI and SUZI can be of great benefit to couples where the man has:
In addition, couples who have had IVF cycles where no fertilisation has occurred, or where there were very low rates of fertilisation, may find ICSI can overcome this problem. The use of micromanipulation techniques is increasing, as are success rates. However, because these techniques are new, assessment of the risks involved is at an early stage. There is some concern that because ICSI involves piercing the egg, this may cause a higher incidence of congenital abnormalities. However, studies vary but most show the risk from IVF/ICSI is no greater than when using conventional IVF alone. With ICSI (and IVF), 'assisted zona hatching' may also be offered, especially to couple where the woman is 38 years old or more, or for frozen embryo replacements. The technique involves using a laser to create a small hole in the zona pellucida of the developing embryo to help it to break out of its shell and implant more easily in the wall of the uterus. Because so few babies (relatively speaking) have been born as a result of IVF/ICSI, much more research will be needed before significant figures are available. However, reflecting these concerns, most clinics will advise couples who conceive through ICSI to have regular ultrasound scans in the early weeks of pregnancy, and many suggest that couples consider an amniocentesis at around 15 weeks. TESA. PESA & MESATESA (Testicular Sperm Aspiration): A needle biopsy of the testicle used to obtain small amounts of sperm. A small incision is made in the scrotal skin and a spring loaded needle is fired through the testicle. Usually does not result in enough sperm to freeze for later use. Any sperm found are used in conjunction with in vitro fertilisation with ICSI. PESA (Percutaneous Epididymal Sperm Aspiration): A small needle is passed directly into the head of the epididymis and fluid is aspirated. MESA (Micro-epididymal Sperm Aspiration): An operation to retrieve sperm from the epididymis in men who have a blocked vas deferens, carried out under general anaesthetic. Sperm taken straight from the epididymis usually have poor motility so doctors usually proceed straight to ICSI on the same day.
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