The luteal phase was supported with progest - eron in two sets . pregenancy was defined as a positive hcg test in urine on day 14 post transfer after embryo transfer . clinical pregnancy was defined as the presence of a gestational sac ( s ) with a viable embryo shown on vaginal ultrasonography performed approximately 28 days after embryo transfer 两组均采用黄体酮进行黄体支持,移植后14天检测晨尿hcg及血p - hcg ,晨尿hcg阳性,血p一hcg 200miu / l ,移植48天后进行: b超检查,见胎囊,胎心,为临床妊娠,所有患者随访至妊娠10周。