What do we see two days after in vitro fertilisation?

The first embryo division (an embryo with two cells or blastomeres) usually occurs 25 hours after fertilisation. Forty eight hours after fertilisation, the second embryo division takes place (embryo with four blastomeres). However, at this point, since not all embryos grow at the same rate, some embryos may have 2, 3, 4 or 5 cells, with different degree of fragmentation between the blastomeres.