The video shows time lapse embryo division and fragmentation development. As the embryo division progresses you can see absorption of the fragments.

Internalization of a Fragment
Category: Embryo Development
Submitted By: Thorir Hardarson, Phd.
Institution: Fertility Center Scandinavia
Time: 0:32

Hardarson T, Löfman C, Coull G et al. 2002 Internalization of cellular fragments in a human embryo: time-lapse recordings. Reproductive BioMedicine Online, Vol. 5, No. 1 36–38; see http://www.rbmonline.com/Article/633 .