To explore the effects of the different administration methods and the different doses of mifepristone for treating patients with termination of pregnancy on their vaginal bleeding time and endometrial receptivity. Methods: The clinical data of 96 patients with termination of pregnancy admitted to the hospital from May 2021 to May 2023 were analyzed retrospectively. According to the different administration of mifepristone, the patients were divided into three groups, which included that 30 patients in group A were given oral mifepristone 200 mg once, 34 patients in group B were given oral mifepristone 150 mg administration in 2 days and 32 patients in group C were given oral mifepristone administration in 2.5 days. The postoperative vaginal bleeding situation, the values of the endometrial receptivity indicators in the 3rd month after abortion, such as endometrial thickness, resistance index (RI) and pulsatility index (PI), and the levels of ovarian function indicators, such as estradiol (E2), progesterone (P) and anti-Mullerian hormone (AMH), the rates of the postoperative complications and drug adverse reactions of the patients were compared among the three groups. Results: The intraoperative vaginal bleeding volume (23.2±3.6 ml), the vaginal bleeding time (4.1±0.9d), the postoperative vaginal bleeding volume (57.7±8.4ml), the menstrual recovery time (25.7±2.4d) of the patients in group A were significantly lower than those (27.0±4.1d, 4.7±1.1 ml, 62.5±9.6d and 28.5±2.7 ml) of the patients in group B and those (27.6±4.1 ml, 5.1±1.1d, 65.3±10.0 ml and 29.6±3.0d) of the
patients in group C (all P<0.05), but which of the patients had no significant differences between group B and group C (P>0.05). In the 3rd month after termination of pregnancy, the endometrial thickness (8.35±0.76mm) of the patients in group A was significantly higher than that (7.84±0.81mm) of the patients in group B and that (7.69±0.88mm) of the patients in group C, the RI value of the patients in group A was significantly lower than that of the patients in group C, and the PI value of the patients in group A was significantly lower than that of the patients in group B and in group C (all P<0.05). There were no significant differences in the levels of E2, AMH and P, and the postoperative complications rate of the patients among the three groups (P>0.05). The incidences of the nausea and vomiting (3.3%), and stomach pain (10.0%) of the patients in group A and those (2.9% and 8.8%) of the patients in group B were significantly lower than those (21.9% and 34.4%) of the patients in group C (all P<0.05). There was no significant difference in the incidences of the diarrhea, dizziness and fatigue of the patients among the three groups (P>0.05). Conclusion: The single high-dose mifepristone is helpful for terminating pregnancy of the patients, but the prolongation of mifepristone used for terminating pregnancy of the patients may lead to the increase of their drug adverse reactions.