Michelle Emblenton, a biochemist at inviTRA, tells us about the IMSI technique:
The field of assisted reproduction is constantly ongoing in improving and innovating techniques with research. A recent technique is called IMSI. This stands for intracytoplasmic morphologically selected sperm injection and is a way of choosing the very best sperm for the in vitro fertilization process. This cutting edge technique uses ultra high magnification levels, over 6,300 times normal levels, to study the sperm and look at their morphology closely before choosing which one will be used for fertilization. This is a great advantage over the more frequently used ICSI technique, which only uses 400 times magnification.
IMSI allows the embryologist to study the sperm in great detail and they will look at the headpiece, the neck piece and the tail. The headpiece should be intact, with an intact nucleus and of an oval shape. The tail needs to be straight and not curved. Additionally, the sperm needs to have its acrosome intact and be of a transparent color. All of these things help the sperm to properly fertilize, penetrate and fertilize the egg. One of the most commonly used techniques in IVF at these days is ICSI (intracytoplasmic sperm injection) in which a sperm cell is selected by the embryologist and is injected directly into the cell. This is done under magnification levels of about 400 times, so it is the embryologist who will select the sperm cell.
By using IMSI, we can better the selection of the sperm cell. One of the drawbacks of the ICSI technique is that the embryologists themselves may have their own selective criteria for choosing a sperm cell. And the advantage of using IMSI is that we can really study the sperm cells in more detail to choose what is indeed the best sperm. As a result of IMSI, we see better success rates in terms of pregnancy and birth rates. By using such high power magnification, the Specialist can actually study inside the sperm cell to check the nucleus is intact and is not broken and that the sperm cell inside and outside is of very good quality and likely to produce good quality embryos following fertilization.
