評估胚胎最重要指標為day2分裂狀況與early cleavage

single PB胚胎不建議植入
<20 h即分裂之胚胎不建議植入
理想PN中有5-7核仁
>35% fragmentation之胚胎其染色體80%異常
fragmentation<40um


http://humrep.oxfordjournals.org/content/26/6/1270.full