MII frozen group (n=73), the GV and MI oocytes first were cultured IVM, then MII oocytes frozen-thawed, observing the oocytes meiotic spindle, performing ICSI;

• MII卵冻融组(n=73),先将GV期和MI期卵子体外成熟培养到MII期进行冻融,将存活的卵子进行纺锤体观察,并行ICSI;