Figure 17

ESHRE zygote scoring system [1]. symmetrical zygotes show two PBs, two centrally located and juxtaposed PNs with distinct membranes, equal size and equivalent numbers and size of NPBs equatorially aligned at the region of membrane juxtaposition (A), non-symmetrical zygotes (differing from the ideal configuration A) (B), and abnormal zygotes with no NPBs and those with a single NPB (C).