Abstract: Objective: To investigate the clinical features and prognostic factors of acute appendicitis during pregnancy.Methods: The clinical data of 94 patients with acute appendicitis during pregnancy admitted to the First Hospital of the University of Science and Technology of China were retrospectively analyzed. The clinical manifestations and physical and chemical examination characteristics of these patients have been summarized. The correlation between the preoperative indicators and the pathological types of appendix, postoperative complications, and unexpected termination of pregnancy were analyzed.Results: Patients with typical symptoms(right lower abdominal pain) and signs(right lower abdominal tenderness) accounted for 92.55% and 94.68%, respectively. The positive rate of B-ultrasound was 51.06%. The average level of preoperative white blood cell(WBC) count is(15.51±4.28)×10⁹/L. The incidence of complicated appendicitis was 30.85%. The WBC count level of complicated appendicitis was higher than that of uncomplicated appendicitis, and the difference was statistically significant[(17.04±4.35)×10⁹/L vs.(14.83±4.09)×10⁹/L, P<0.05]. The incidence of complicated appendicitis on day 1, 2, and 3 were 10.00%, 52.38%, 92.31%, respectively, and the differences were statistically significant(P<0.05). The pathological type of the appendix had no correlation with the patient's age, B-ultrasound results, pregnancy history and gestational stages(P>0.05). The overall incidence of complications and unexpected termination of pregnancy were 9.57% and 8.51%, respectively. There was no significant difference in the incidence of postoperative complications and unexpected termination of pregnancy on the first and second days of the onset(3.33% vs. 4.76%, 1.67% vs. 4.76%, P>0.05), and they were significantly higher on the third day of onset(46.15%, 46.15%), compared with the first and second days of onset, the differences were statistically significant(P<0.05). Postoperative complications and unexpected termination of pregnancy were not related to the patient's age, WBC level, B-ultrasound results, pregnancy history and gestational stages(P>0.05).Conclusion: The diagnosis of acute appendicitis during pregnancy is still mainly based on typical clinical symptoms and signs. The diagnostic value of B-ultrasound is limited. WBC level can be used as a reference parameter for the severity of appendix pathology. Early surgery can reduce the incidence of postoperative complications and unexpected termination of pregnancy. For suspected patients who have difficulty in diagnosis, clinical observation within 2 days after the onset is relatively safe.