Hallo,
hier der Auszug der Studie eines israelischen Wissenschaftlers über die IMSI.
Gleich eines zu Beginn, auch diese Methode scheint nicht der Goldene Weg zu sein. Die Schwangerschaftsquote wurde zwar erhöht, aber nicht so signifikant, als dass man diese Methode als Mittel der Wahl ansehen müsste. Mit Sicherheit hat sie ihre Berechtigung, aber wie der Verfasser selbst sagt, müssen noch weitere Studien erfolgen.
An Israeli team of male infertility experts have developed a new step in the reproductive medical technique of intracytoplasmic sperm injection (ICSI) that they say improves the method’s pregnancy rate and the "take home baby" rate.
Professor Benjamin Bartoov, a biochemist and andrologist at Bar-Ilan University in Ramat Gan, developed the new method, which is known as intracytoplasmic morphologically selected sperm injection (IMSI) and which has resulted in the births of 101 babies in the past four years. .....
When ICSI is used in the routine way, one sperm is taken from the sperm pool after routine selection under a regular microscope that magnifies it 200 to 400 times.
Professor Bartoov uses a high magnification method, which multiplies the image of individual sperm up to 6000 times through high power light microscopy. This makes it possible to discard sperm whose nucleii have an abnormal shape or contents and is thus, he found, much less likely to produce a healthy embryo with a good chance of developing properly in the uterus.
An article on the method and its results were published last year by Professor Bartoov and eight colleagues from Bar-Ilan University and the Herzliya Medical Centre in Fertility and Sterility. In the study, 50 couples who had had at least two previous failed attempts at fertilisation with ICSI underwent a single ICSI trial preceded by morphological selection of spermatozoa with normal nuclei. They were matched with 50 couples who underwent a routine ICSI procedure. The matching study revealed that the pregnancy rate after modified ICSI was significantly higher than that of the routine ICSI procedure (66% versus 30%).
Since the study was conducted, the team has carried out further IMSI procedures. The team says that taking their figures as a whole the technique has improved the usual in vitro fertilisation pregnancy rate to 48% and the take home baby rate to 40%, compared with the normal rate for in vitro fertilisation of 20-30% (in Israel, the United States, and western Europe) and a take home baby rate of about 20%.
Professor Bartoov invested more than two decades in the Bar-Ilan Quantitative Ultra-Morphology system, which determines fertility potential by examining the surface and internal shape of seven subcellular cell organelles of unstained individual sperm cells.
The optimum nucleus is smooth and symmetric, with an oval configuration. Any extrusion or indentation of the nuclear mass is considered a malformation, the team wrote. In addition, the chromatin mass in the nucleus should contain no more than one vacuole occupying less than 4% of its area. The team also determined an optimal length and width for the most effective sperm.
The freshly ejaculated sperm cells with the greatest fertility potential are placed in a glass dish and then into a special cooler that Professor Bartoov designed; then they are transferred to a hospital in vitro fertilisation clinic. This procedure is carefully timed so that the selected sperm arrive at the same time as the retrieval of the woman’s ova to be injected by embryologists into the cytoplasm of the egg.
The team concluded that the "fine morphological state of the sperm nucleus is an important factor in achieving pregnancy" if ICSI fails, and that a double blind, multicentre study should be performed to validate their conclusions.
