ICSI, intracytoplasmic sperm injection, was developed in 1988 as a treatment for male infertility, i.e. men with very poor sperm parameters, to treat fertilization failure with IVF.
ICSI is now routinely used in many IVF programmes as the fertilisation rate is higher than with standard fertilisation techniques and pregnancy rates are higher. There is inadequate information about a possible increase in birth defects with ICSI. There appears to be an increased risk of twins with ICSI, especially with blastocyst transfer. This can be as high as 2%.