Day 4 - the day of rest

Day 4 - The day of rest

What is happening?

The embryos are undergoing a very important transition process we call compaction and early blastulation so that they form blastocysts. Compaction commences when the embryo forms a ´morula´, a stage in which the embryo usually has 16 or more cells and they start to come very close to each other to form a mass resembling a raspberry.

Once the embryo has become a compacted morula, a cavity starts to form inside it, a process called blastulation. This cavity fills with liquid and as it grows the embryo will form a blastocyst on day 5 or day 6 of development.

What should I expect?

During day four we perform no checks as it is hard for us to grade them with so many changes going on at this point. We prefer to leave them undisturbed in the incubator. Therefore, we will not get in touch with you today.

If your treatment involves the use of Embryoscope time lapse technology, then we do things a little different. We can see the formation of the morula and the blastulation. Visit our section on Embryoscope to see how it works and what we do with it.