First of all, a 0.7 cm endometrium is not suitable for embryo transfer and the transfer failure rate is high. The embryo transfer needs to be done at the right time, which is clinically known as the “embryo transfer window”, in order for the embryo to adhere to the endometrium and successfully implant. Currently, there are criteria for defining the window period for transfer, and only when the ultrasound examination indicates that the endometrial thickness is between 9-10mm is the window period suitable for transfer. If the standard has not been reached, it is recommended to continue dynamic observation or to receive artificial cycle therapy until the time is ripe for transplantation.