Sperm quality is undoubtedly one of the most important determinants in the quality of the pregnancy during an IVF/ICSI procedure. Intracytoplasmic sperm injection (ICSI), a method of choice to treat male infertility, bypasses natural sperm selection.
It is known that sperm morphology or shape, evaluation of individual motile spermatozoa before ICSI is limited because of the low magnification used in routine microscopy.
The introduction of computer-enhanced digital microscopy allows for magnification of more than 6000 times, and this technique named `motile sperm organelle morphology examination’ (MSOME) was developed to examine and select the sperm cells, potentially selectable for ICSI.
This means sperm with major morphological abnormalities can be actively avoided. With MSOME, subtle morphological features, such as abnormal proportions of sperm head size, midpiece abnormalities and the presence of vacuoles in the sperm head have been characterized.
The microinjection of spermatozoa, preselected on the morphology and minimal presence of head vacuoles, termed `intracytoplasmic morphologically selected sperm injection’ (IMSI) has been reported to increase pregnancy rates and reduce spontaneous pregnancy loss in ICSI cycles.
While data continues to be gathered it would appear abnormal sperm morphology can be related to other defects including damaged DNA, chromosomal abnormalities and cell structural deficiency. Vacuoles on the sperm appear to have a negative influence on embryo development and these may be linked to sperm DNA damage.
During an IMSI procedure, the female partner is managed in the same way as other IVF patients, is given ovulation-inducing drugs, and the resulting mature eggs are then harvested from her ovaries and prepared for fertilization in the laboratory.
Then using the expensive, advanced high-powered microscope to examine the male partner’s semen sample the sperm cells are carefully examined by skilled scientific staff.
The selected or desired sperm cell is taken up in a long, thin, hollow needle ready to be injected into the egg. The egg is held steady with a special pipette, and then the needle containing the selected sperm cell is pushed through the outer shell of the egg and into its inner area, where fertilization can take place.
The eggs and sperm are then left for 24 hours, during with fertilization is likely to occur. The fertilized eggs (embryos) are transferred back to the woman’s uterus where hopefully at least one will implant and result in a viable pregnancy.
IMSI procedure may be beneficial for embryo development in patients with
Currently, there is no evidence to suggest there needs to be a male age restriction. There is however a risk as in general IVF procedures relating to multiple births if more than 1 embryo is transferred during the procedure.
The likelihood of achieving a viable pregnancy is higher with better quality embryos along with other factors.
Using IMSI procedure and increasing the likelihood of gaining better quality embryos than we would have otherwise, there is expectation of a better pregnancy outcome. IMSI like other IVF procedures does not guarantee the offspring will be free of genetic disease and therefore you need to consider any proposed procedure acceptable to you.
Mr Gulam Bahadur