Objective ·To evaluate endometrial receptivity in patients with hereditary thrombophilia [i.e., hereditary prethrombotic state (PTS)] and explore the therapeutic effect of low-dose aspirin (LDA) using uterine color Doppler ultrasound blood flow parameter detection. Methods ·A total of 265 patients who attended the Department of Obstetrics and Gynecology, Renji Hospital, Shanghai Jiao Tong University School of Medicine from January 2023 to December 2024 due to infertility or a history of adverse pregnancy outcomes were enrolled as research subjects. Based on the inclusion and exclusion criteria, 191 patients were finally included in the study. According to the Expert Consensus on the Diagnosis of Causes of Recurrent Miscarriage (2022 edition), the patients were divided into three groups: the hereditary PTS group (n=71), the antiphospholipid syndrome (APS) group (n=70), and the control group (n=50). Patients in the hereditary PTS and APS groups were treated with LDA continuously for 2 months, while the control group did not receive LDA treatment. The main observation indicators included uterine artery blood flow parameters [pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio (S/D)] and endometrial parameters [endometrial thickness and endometrial blood flow parameters (PI, RI, and S/D). Before LDA treatment, color Doppler ultrasound was used to detect the main observation indicators in the three groups of patients. After completing LDA treatment, patients in the hereditary PTS and APS groups underwent a second measurement. The ultrasonographic parameters of the three groups before treatment were compared to analyze the effects of hereditary PTS on endometrial thickness and blood perfusion. In addition, the ultrasonographic parameters of the hereditary PTS group and APS group before and after treatment were compared to evaluate the therapeutic efficacy of LDA. Results ·Before LDA treatment, compared with the control group, patients in the APS group and hereditary PTS group exhibited higher levels of endometrial blood flow parameters (PI, RI, S/D) and uterine artery blood flow parameters (RI, S/D) (P<0.05). After LDA treatment, patients in the hereditary PTS group showed decreases in endometrial blood flow PI, as well as uterine artery blood flow PI, RI, and S/D (P<0.05). Conclusion ·Patients with hereditary PTS have endometrial hypoperfusion, and LDA treatment can significantly improve endometrial blood flow and uterine artery perfusion in these patients, which has potential clinical value in enhancing their endometrial receptivity.