If the patient’s menstrual cycle is irregular, we can thaw the embryos for transfer using the method of descending and then artificial cycle. The specific procedure is as follows: come to the hospital between the second and fifth day of menstruation to check the ultrasound, when the conditions are suitable, take oral Mafulon for 21 days, and when 2 or 3 tablets of Mafulon are left, take a down-regulation injection, then come to the hospital for 2 weeks to have blood tests for sex hormones and ultrasound, when the conditions are up to standard, you can take estrogen to promote the growth of endometrium, usually after 14-20 days the endometrium can reach the standard 8mm for embryo transfer. After 14-20 days, the endometrial lining can reach the standard of 8mm for embryo transfer, and then it is time to schedule the thawing and transfer. In addition, if the menstrual cycle is irregular, we can also use the ovulation promotion method to transfer frozen embryos. The procedure is as follows: come to the hospital between the second and fifth day of menstruation for an ultrasound, and start taking oral ovulation medication for 5-7 days according to the condition of the follicles, and check the follicle growth after 7 days with ultrasound. When the LH ovulation peak is positive, the endometrial lining can be transformed and the mature follicles can be promoted to be expelled. If the follicles cannot be discharged during the examination, or if the follicles stop growing, the frozen embryo transfer should be abandoned for that month; for follicular luteinization, the frozen embryo transfer also has a certain success rate.