Oocyte activation is characterized by a dramatical rise in intracellular calcium concentration.
The initial step of the oocyte activation is triggered by a sperm protein (PLZzeta). The major event is the Ca++ release from internal calcium stores of the oocyte.
This starts within a few minutes after spermatozoa and egg fusion. During ICSI, this trigger function is taken over by an artifi cial calcium infl ux from the surrounding medium produced by the micromanipulation procedure itself. After this, a series of short high frequent Ca++ oscillations follow and continue for several hours after fertilization.
The reason for unfertilizated Oocytes after ICSI are
- Oocyte related
- Sperm related
A diagnostic test for the routine laboratory is so far non-existant. In the literature, a hetereologous ICSI test by injection of the human sperm cells in mouse oocytes is described, but this is, labor intensive and not allowed in several countries.
The fertilization rate can be enhanced by mimicking the physiological cell – signaling to the oocyte activation using an activation agent like the Ca++ Ionophore. Electric activation is also effective.
We are recommending the Ca++ Ionophore for those couples who underwent a previous ICSI cycle with a low fertilization rate, which means fewer than 50%.
If you see our small study over 75 patients, you can increase the fertilization rates for patients with:
- A complete fertilization failure after ICSI
- A low fertilization rate after ICSI
- Severe male factor infertility.
Advantages for the IVF Lab:
The GM508 Cult-active treatment gives normal rates of implantation and pregnancy rates.
The GM508 Cult-active is easy to apply, to put the oocytes into the Ca++ Ionophore GM508 Cultactive after the ICSI procedure for 15 minutes. Then wash the oocytes intensively in equilibrated
Culture media before cultivating them.
The embryologists can store the GM508 Cult-active in the laboratory because it has a shelf life of
6 months.
For fi nding the well-fi tting patient for Cult-active, it is important that the embryologist checks the
fertilization rates of the couple´s previous cycles.