In today’s post we will discuss the next steps in the IVF process that takes place behind the embryology lab doors. If you are just joining us you might want to start with part 1, which talks about what goes on in the lab on retrieval day, and/or get caught up with part 2, which talks about the fertilization process.
We start the day carrying out a check on all the equipment before observing any of the eggs and embryos – making sure that the temperatures and gas levels are all within the strict settings that we have established. Then we can start the work of checking on everything that has happened overnight. The first check we perform on the day after a retrieval is a called the “fert check” or fertilization check.
When we carry out the fertilization check we are looking for the appearance of 2 pronuclei which shows us that the sperm has entered the egg, and that it has been recognized and processed by the egg. In the case of the eggs that were fertilized by conventional IVF we have to remove what is left of the cumulus cells (the layer of cells that surround the ova, or egg) after the majority of them have fallen away after being incubated with the sperm. In the case of the ones that were fertilized by ICSI we just have to look, seeing as though the cumulus has already been removed as part of the ICSI procedure.
Once we have established that an egg has been fertilized it is moved into a fresh drop of culture media, which has got just the right nutrients for its developmental needs. From this point on the embryos are cultured individually, one embryo per drop – that way we can keep an eye on who is doing what and when! Each drop has its own number assigned to it, and it allows us to compile all the data that we collect about it.
Once we have completed all the initial checks in the laboratory for the morning then we can come out and make some phone calls. I know that you are going to be very anxious waiting to hear what has happened, so we really do try our best to get that call made as early as we can. At this stage of the IVF process there isn’t really a huge amount of information that we can give you, just a confirmation of how many have normally fertilized. Most people ask if we can tell what the quality of them is at that point, and as much as I would love to be able to do that there isn’t much to tell.
We do look at them again towards the end of the day on fertilization check day, this time to see which of them are trying to move forward and divide first. Unfortunately, there isn’t a huge amount of direct correlation between anyone of the numerous pieces of information that we collect about the embryos, but we compile it all in order to get a better picture of what the embryos look like.
If at any time you want a phone call to check in on them, then we will be more than happy to do that for you. However, you have to remember that we think that they are going to be much happier left in the incubator, so we keep the checks limited to what is going to help us get a valid picture of their development.
Stay tuned for the next installment of my Behind the Laboratory series where I will talk about what happens to the embryo next. If you haven’t done so already please like our Facebook fan page! We post lots of cool new info about the field.
