If the endometrial thickness is relatively slow to grow through ultrasound monitoring, clinically it may be due to the following reasons: the first one is caused by endocrine disorders, especially when estradiol is insufficient, the endometrial growth is relatively slow. The second reason is the history of previous uterine operations, such as abortion or curettage or diagnostic curettage, which caused damage to the endometrium and resulted in incomplete adhesions. In this case, hysteroscopy is needed to separate the adherent tissues and then further treatment is needed so that the endometrium can be restored to normal. Therefore, a comprehensive analysis of the medical history should be taken into account and then the appropriate treatment should be given.