In case the sperm sample is of lesser quality or there is a history of failure to fertilise following classic IVF, intra-cytoplasmic sperm injection (ICSI) is applied.
This is the technique that makes the equation
one oocyte + one sperm = one embryo
come true and overcomes low sperm count or low motility issues that usually cause male infertility.
This technique entails the selection of one sperm by the embryologists, based on its morphology and motility, as well as the injection of the sperm in question into an oocyte. The whole procedure is performed with the aid of a powerful microscope and special micro-manipulators.
This technique has offered a solution to couples with a severe male infertility factor. Only one sperm, even with low motility, is required, in order to fertilise the oocyte. Fertilisation rates following ICSI reach 65-75%, i.e. even with this method, there is a percentage of failed fertilisation, especially if:
• Oocytes are fragile or immature, i.e. of low quality; in that case, their manipulation while applying the method further aggravates them.
• There is a high percentage of abnormal sperm morphology.
The question that often occurs is the following: “why isn’t ICSI applied in all IVF cycles, so as to avoid failed fertilisation with classic IVF?” At “gennima”, Mr. Evripidis Mantoudis believes that, although ICSI is a technique that has offered a solution in very severe cases of male infertility, it is not a panacea and must only be used where it is truly substantial and meaningful.
ICSI is a safe method, as proved by thousands of children born across the world. Children born with the aid of ICSI are no different from those born following classic IVF. For more details, please read below.
Safety of ICSI
ICSI is an innovative technique used to treat male infertility. Like all new assisted reproduction methods, ICSI, too, has been thoroughly studied, mainly with regards to the health of the children born with the use of the technique in question.
By now, thousands of children have been born in Greece and across the world with the help of ICSI, often combined with techniques of sperm retrieval from the epididymis or testicles, so as to treat male infertility. These children are healthy and no different from the children born following classic IVF. However, there is a marginal increase in abnormalities of the urinary system due to paternal infertility. Finally, with regards to mental development, results in children born following ICSI and those born with the aid of classic IVF are similar. (“A review of ten years experience of ICSI” P.Devroey and A.Van Steirteghem Human Reproduction Update, Vol.10, No.1 pp. 19-28, 2004)
In most studies until today, the congenital abnormality rate in children born following ICSI is the same as in children born following classic IVF or in the general population (2-3%). Most of the abnormalities observed are due to preterm labour after multiple pregnancy. The most common abnormality is hypospadias, probably related to paternal infertility. Today, it is believed that all problems in children born with the aid of ICSI are rather due to problems in the father’s sperm (genetic material) than to the method of ICSI itself.
Note: hypospadias is a defect of the urinary system concerning the boys’ urethra. Most of the times, this defect is easily restored with a minor surgery, approximately at the age of 2.
The analysis of genetic material in children born following ICSI has shown in the past increased problems in genetic chromosomes (one X lacking or an additional X or Y existing in 0.83% or 8.3‰, versus 0.2% in the general population). The structural abnormality rate in chromosomes of children born following micro – insemination was also found to be increased (0.36% versus 0.07% in the general population), especially in case of paternal oligo-astheno-terato-zoospermia. Another study reports that all cases of abnormalities in genetic chromosomes are of paternal origin. In any case, these abnormalities are rare. To better understand how rare they are, one must consider that 0.36% (or 3.6‰) of structural chromosomal abnormalities means that among 1.000 children born with the aid of ICSI there are 3 with one such abnormality (most of the times, not affecting the child’s health). These chromosomal abnormalities may occur as a consequence of the increased abnormality rate in genetic chromosomes in the sperm of men who need ICSI.
Moreover, several studies including large populations of children born by means of ICSI, have been carried out, for the purpose of examining their mental development (at the age of 1-2 or older). Children born following ICSI didn’t seem to have any difference from those born following classic IVF or natural conception. The possibility of preterm birth and low birth weight seems to constitute a more significant factor in these children, i.e. preterm birth affects a child more than ICSI does.
Finally, the procedure of ICSI has been accused of affecting embryo culture. Some studies suggest that a smaller percentage of embryos created with the aid of ICSI reach the blastocyst stage. This must be further explored, as implantation and pregnancy rates following ICSI are the same with those following classic IVF.
ICSI has helped many couples with severe male infertility to have children. Even in cases of azoospermia, there have been developed several techniques of sperm retrieval from the epididymis or the testicles, combined with ICSI. Moreover, patients with very severe sperm problems must unsderstand that they may have genetic abnormalities in their sperm, which may thus be transmitted to their offspring. These couples must be informed in detail with regards to the reasons of infertility, the odds of a healthy pregnancy and the possibilities of embryo diagnosis.
Finally, long-term consequences of ICSI (e.g. impact on the subsequent development) must be studied over the course of time. Each couple must be extensively informed in advance. For that reason, ICSI mustn’t be indiscriminately used; however, it constitutes a particularly effective treatment of male infertility.
For more details, please read the relevant article:
«Reproductive Technologies for Male Infertility»
Khorram O. et al 2001 The Journal of Clinical Endocrinology & Metabolism 86(6):2373-2379]