The original purpose of fertility preservation treatment for endometrial cancer is to preserve the hope of fertility for patients with fertility requirements, so the issue of pregnancy after successful conservative treatment is crucial. Most scholars recommend assisted reproduction as soon as possible after a completely normal endometrial biopsy, which can increase the success rate of pregnancy and reduce the recurrence of tumor. Some scholars believe that natural conception is possible and can save the high cost of assisted reproduction. Therefore, there is still no definite conclusion as to which patients can attempt natural conception and its safe duration. However, most studies support the use of assisted reproductive techniques (including ovulation and IVF) in patients with combined infertility and anovulatory disorders such as polycystic ovary syndrome, as soon as possible after the endometrial cancer has gone into remission, because of the difficulty of conceiving naturally. Patients with polycystic ovary syndrome are mostly young, obese, anovulatory, and have sporadic menstruation. Obesity or anovulation leads to endocrine disorders and endometrial hyperplasia and endometrial cancer are prone to occur due to long-term stimulation of endometrium by persistent high estrogen without progesterone counteracting. The recurrence rate of endometrial cancer patients with combined obesity is significantly higher after conservative treatment. Thus, it is unwise to wait for a spontaneous pregnancy after successful conservative treatment. For spontaneous pregnancy or failed assisted conception after endometrial reversal, and not immediately assisted conception again, but with normal clinical and imaging examinations and endometrial biopsy, is progestogen maintenance therapy required? What is the appropriate timing for pregnancy? Tumor recurrence is as high as 69% in patients who are not maintained after successful conservative treatment or who are not immediately pregnant, so progestin maintenance therapy is necessary to significantly reduce the risk of tumor recurrence. The application of progestogen-releasing IUDs to prevent tumor recurrence has also been reported. The precise timing of the appropriate timing of pregnancy remains a problem for clinicians.