Fig. 1.

Morphological characteristics and kinetic parameter abnormities observed by time-lapse imaging. A Representative images show three consecutive occurrences of division and the production of eight blastomeres in the control zygote (a–e), as well as three abnormal cleavage patterns during embryonic development of the patients’ zygotes. NC, normal cleavage; PN, pronucleus; DA, developmental arrest; DC, direct cleavage; FC, failed cytokinesis; RC, reverse cleavage; BF, big fragment; UB, uneven blastomeres; -b, the larger blastomeres of the UB; -s, the smaller blastomeres of the UB. The arrow indicates the PN, and the arrowhead indicates the three nuclei produced despite the first cytokinesis failure. B Kinetic parameters such as the tPNF(a), t2(b) and ECC1(c) delays in the patients’ zygotes. Dates are shown as the average