超過一半胚葉細胞呈現染色體異常，若異常之胚葉細胞屬於發育為日後胎盤之TEcell，此胚胎仍有可能形成正常染色體之胚胎
此理論說明PGD之嚴重盲點，畢竟PGD取的細胞為日後發育為胎盤之TE cell
也沒有大規模統計這些PGD異常胚胎ICMcell是否均異常


http://link.springer.com/article/10.1007%2Fs10815-016-0845-7

Fig. 1

Early human development. a The zygote possesses one pronucleus containing egg chromosomes and another pronucleus containing sperm chromosomes. Both sets of chromosomes are duplicated before the first cleavage to two cells. The morula forms at the 8- to 16-cell stages, trapping one or two cells inside that undergo commitment to become the inner cell mass (ICM) within the blastocyst. The ICM gives rise to the fetus. The outer cells of the blastocyst become committed to trophoblast, precursor to the placenta. b Theoretical aneuploidy in early development. The scheme depicts the highest rate of aneuploidy (purple cells) that could form the ICM from a euploid cell (green) and produce a normal fetus. This theory is supported by several lines of evidence, including chromosomal analyses that reveal both aneuploid and euploid cells in human blastocysts