ICSI involves the direct injection of a single sperm into each egg under direct microscopic vision and requires a high level of technical expertise. In fact, even when there is an absence of sperm in the ejaculate such as occurs in cases of congenital absence of the Vas deferens (when a man is born without these major sperm collecting ducts), in cases where the vasa deferentia (ducts that carry the sperm from the testicles to the penile urethra for ejaculation) are obstructed (such as follwing vasectomy or trauma), and in some cases of testicular failure or where the man has impotency, ICSI can be performed with sperm obtained through Testicular Sperm Extraction (TESE), or aspiration (TESA). In such cases, the birth rate is usually no different than when IVF is performed for indications other than male infertility.
There seems to be quite a bit of speculation about the rate of birth defects associated with children conceived through ICSI fertilization. Here are some facts:
- The performance of ICSI in cases of male factor infertility has been shown to slightly increase the risk of certain embryo chromosome deletions (leading to a slight increase in early miscarriages).
- There is some evidence that there is an increased potential for a resulting male offspring to have male infertility in later life
- There is no evidence of any significant increase in the incidence of serious birth defects attributable to the ICSI procedure itself.
- More relevant is the fact that when ICSI is performed for indications OTHER THAN male infertility there is NO reported increase in the risk of subsequent embryo chromosome deletions, miscarriages or in the incidence of subsequent male factor infertility in the offspring.
A relatively recent study was performed in Sweden, in which 542 children conceived naturally were compared with 941 children conceived through IVF (440 by conventional IVF & 541via ICSI). The following parameters were assessed at birth and during the first 5 years of life:
- Birth health and obstetrical complications
- Birth defects or malformations
- Family relationships
- Physical development
- Mental, psychological, and social development
No major differences in birth weight, growth, total IQ, motor development, and behavior problems or parental stress were found between the children conceived with infertility treatments and those conceived naturally.
Another major advantage of doing conventional ICSI is that it affords the opportunity to remove the complex of cells that envelop the harvested egg (cumulus) and so enable the embryologist to evaluate microscopic paramaters that point to maturity. This cannot be done with conventional IVF as the removal of these cells would virtually preclude conventional fertilization in the petri dish.
About 12-15% of conventional IVF is associated with unanticipated absent or poor fertilization. In fact new tests of sperm such as the sperm chromatin structure assay (SCSA) and the sperm DNA integrity assay (SDIA) have demonstrated that DNA damage may be present in sperm from men ith both normal and abnormal semen analyses and that male infertility is equally prevalent in such cases. Thus, disappointments associated with unanticipated failed fertilization that might be averted through routine performance of ICSI. There simply does not seem to be any practical downside to this aproach which is now routine throughout the SIRM system.
There are no data suggesting that ICSI should not be performed in all cases of in-vitro conception. In all cases, female factor or male factor (normal or abnormal spermatozoa), the use of ICSI bypasses most dysfunctions, eliminating the majority of barriers to fertilization. If fertilization does still not occur, then there is a greater chance of it being a genetic reason, and the risk of genetic abnormalities in normal spermatozoa should not be of greater concern than those in abnormal spermatozoa.
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12 comments:
This was very interesting. When my husband and I underwent IVF the first time, our clinic did half ICSI and half natural fertilization for the 18 harvested eggs. What do you know that they fertilized at the same rate! Exactly 7 ICSI and 7 natural.
Thanks for your blogs, they are so informative.
Thank you for your comment.
I appreciate it!
Geoff Sher
Hi Dr. Sher,
Is it true that ICSI is more likely to result in a boy vs girl, I read something about the male sperm swim more quickly or something like that...also, is it true that ICSI is more likely to lead to twins?
thank you
Neither are true!
Geoff Sher
Does the ICSI process increase the cost of IVF alot? My husband has only 3% normal morphology so we have been informed that this is our only hope.
ICSI is usualy charged for as an additional cost, but the amount varies from one center to another..ranging from about $1,000 to $2500.
Since we at SIRM advocate ICSI for ALL cases, we often do not charge for it unless it is being done for male factor, women over 40Y, women with Polycystic Ovarian Syndrome who tend to have eggs with hardened or thickened envelopments (Zona's).
Geoff Sher
I'm interested in your response to the most recent ART stats released by CDC (http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5805a1.htm). In that report, they state the following:
The use of ICSI in the absence of male factor infertility in women considered difficult to treat was evaluated separately. These groups included women who underwent previous ART cycles but had no previous pregnancies or births, women diagnosed with diminished ovarian reserve, and ones with fewer than five eggs retrieved. Within each of these groups, age-specific--live-birth rates for IVF-ET with and without ICSI were examined. In all but four cases, women who used IVF with ICSI had lower live-birth rates than women who used IVF without ICSI. The four exceptions were: 1) women aged <35 years who had previous ART cycles but no previous pregnancies or births; 2) women aged >42 years who had previous ART cycles but no previous pregnancies or births; 3) women aged 41--42 years with fewer than five eggs retrieved; and 4) women aged 41--42 years with diminished ovarian reserve. However, in all other cases, the pattern of these results is consistent with the findings presented in this report (Table 4). Additional analyses also fail to support a clear advantage in using ICSI when treating couples with no indication of male factor infertility. After adjusting for female prognosis factors and types of IVF procedures, cycles using ICSI with no indication of male-factor infertility were less likely to fail before transfer but more likely to result in implantation failure, pregnancy loss, and a lower overall chance of a live birth delivery. ICSI effects on the next cycle were slightly improved but not better than those without using ICSI.
It is not possible to accurately evaluate egg quality and maturity unless you can see the 1st polar body (PB-1)immediately under the zona pellucida (the envelopment of the egg). Visualization of PB-1 requires that you strip away the cluster of cells (cumulus oophorus) that surrounds the egg. Having done so, successful fertilization of the egg mandates that ICSI be done.
Several studies have confirmed that there is no disadvantage in doing routine ICSI. While there can be no argument that ICSI is needed in male factor infertility, and in cases where the zona pellucida is thick and/or hardened (e,g. in women over 40 and in cases of PCOS). Since doing ICSI in other cases, would do no harm and by doing ICSI routinely we are better able to assess egg quality and maturity, I prefer to do ICSI as a matter of routine. However, in such cases,I do not charge extra for doing ICSI.
Geoff Sher
Really interesting stuff, thank you. You say that ICSI removes the vast majority of barriers to fertilization, except genetic reasons. Does that mean that a man can have a genetic problem that completely inhibits sperm's ability to fertilize eggs? Is there any way to test for this?
The best test is the Sperm Chromatin Structure assay (SCSA). Do not waste your time doing sperm chromosome tests.
Geoff sher
Is the "hamster egg test" an accurate test proving that ICSI should be done with IVF? My husband had one done, showing that his sperm only penetrated 30% of the hamster eggs. I have heard different opinions on this test, and if we should do ICSI with our IVF or not. What is your opinion?? I'm trying to figure if the micro-IVF would be worth it to us, as all of the other requirements are met for this procedure.
I do not have much faith in the hamster egg penetrationtest and do not order it at all.
Geoff Sher
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