Abstract:ObjectiveTo explore the application value of transvaginal ultrasound combined with serum levels of vascular endothelial growth factor(VEGF) and estradiol(E2) in the early diagnosis of ectopic pregnancy. Methods A total of 165 patients with suspected ectopic pregnancy visiting to the 904th Hospital of the Joint Logistics Support Force of the Chinese PLA between January 2017 and January 2021 were selected as the research subjects. Pathological diagnosis or follow-up examination were performed to analyze the confirmed diagnosis of ectopic pregnancy. According to the pregnancy outcomes, the patients were divided into ectopic pregnancy group(n=98) and non-ectopic pregnancy group(n=67). The serum VEGF and E2 levels and the ultrasound diagnostic parameters ［endometrial thickness, resistance index(RI) and pulsatility index(PI)］ were compared between two groups at enrollment.Pearson correlation coefficient analysis was used to analyze the associations of ultrasound indicators with the levels of serum VEGF and E2. Receiver operating characteristic(ROC) curve was drawn to judge the diagnostic efficiency of combined detection of transvaginal ultrasound and serum VEGF and E2 levels in the early stage of ectopic pregnancy. Results The serum VEGF level, RI and PI in ectopic pregnancy group were significantly higher than those in non-ectopic pregnancy group(P＜0.01), and the serum E2 level and endometrial thickness were significantly lower than those in non-ectopic pregnancy group(P＜0.01). Pearson correlation coefficient analysis showed that serum VEGF level was significantly positively correlated with RI and PI (r=0.403, 0.194, P<0.05), and was significantly negatively correlated with endometrial thickness (r=-0.651, P＜0.01). Serum E2 level was significantly negatively correlated with RI and PI (r=-0.518, -0.401, P<0.01), and was significantly positively correlated with endometrial thickness(r=0.820, P＜0.01). The diagnostic efficiency of combined detection of transvaginal ultrasound(RI,PI) with VEGF, E2 and endometrial thickness was significantly better than that of each indicator detected alone in the early stage of ectopic pregnancy, with AUC of 0.936 and specificity of 91.00%. Conclusion Transvaginal ultrasound combined with serum VEGF and E2 detection can significantly improve the early diagnostic efficiency of ectopic pregnancy.