My heart is calm. I have been patiently waiting for the call from the doctor to let us know how many of our little cells have turned into blastocysts and are ready for biopsy and being frozen.
I try not to read all the different experiences people share online of how many eggs retrieved, how many fertilized, how many make it to day 5 & 6, etc… but it’s hard not to look.
These last few days have felt deflating. In my mind, I have obtained a goal (of sorts), something I was focused on for many weeks, and now I just sit and wait.
My body is recovering, but still not back to normal. I continue to reheat the rice-hot pack in the microwave and melt into the couch.
We receive a call, today is day 5. It’s nurse Christine calling to report 1 of our eggs have reached blastocyst stage so they have biopsied it and put it in the freezer (my heart drops… only 1).
The remaining 11 are still under observation and they will call us tomorrow with the final count.
Oh, my nerves!
I continue to trust in this process… the process I cannot control and have to simply accept.
The following is taken from Fertility Smarts to help explain the process:
On Day 5, embryos that have continued to grow to become blastocysts will have formed a fluid-filled cavity in the center of the embryo surrounded by a flat layer of cells called the trophectoderm (the part that makes the placenta). These embryos should also have a clump of cells called the inner cell mass (the part that makes the baby). Blastocyst embryos have a more complicated grading system based on 3 factors:
- The size of the embryo – based on the degree of expansion of the cavity (graded 2-6)
- Appearance of the inner cell mass cells (graded A-C)
- Appearance of the trophectoderm layer of cells (graded A-C)
Therefore an embryo with a grade of 4AA would be classed as a good quality embryo. Anything with a B grade is classed as average and a C grade would be quite poor quality.
Embryo grading is not an exact science and it just helps us to get an overall picture of the appearance of an embryo. Grading helps the embryologist to choose which embryo to transfer within your group of embryos.
Embryos with a higher grade are more likely to implant with the uterine lining, most likely because these embryos have a higher chance of being chromosomally normal. In other words, not all embryos are created equally and it is possible to select the genetically normal embryos that are more likely to grow.
What if my embryos have a poor grading?
Most people have a range of grades within their group of embryos from an IVF cycle and the embryologist will pick the best ones out of that particular group. We have seen babies born from different grades of embryos, so try not to focus on the numbers too much.
Although lower grade embryos have a less of a chance of implanting than their more handsome counterparts, it’s still possible to achieve a pregnancy from embryos that are not ideal when viewed under a microscope.
Try not to over analyze the exact grade of your embryos as we have seen babies born from all grades of viable embryos.
On Day 5 we know:
- The number of embryos that have continued to grow and the quality of these embryos.
- On average, only half of all Day 3 embryos will continue to grow to the blastocyst stage and the other half will stop growing after Day 3. Embryos usually stop growing because there is something wrong with their chromosomes. If an embryo stops growing in the lab it would most likely not have made a baby if we had transferred it.
- Not all embryos grow at the same rate. Some will grow faster and be ready for transfer or freezing by Day 5 and some will need another day’s growth to get to an advanced stage. This is a normal growth pattern.
- The best embryos are either transferred or frozen on Day 5 according to your clinic’s policy. In general, pregnancy rates are better when blastocyst stage embryos are transferred rather than Day 2-3 stage embryos.
Any embryos that are frozen are kept in the lab storage tanks until you need them. Any remaining slower growing embryos are kept in the lab overnight and there may or may not be more embryos to freeze Day 6.