Objective To investigate the effects of Zishenyutong pill combined with allylestradiol tablet on patients with threatened abortion (TA). Methods 104 patients with TA treated in our hospital from April 2022 to February 2024 were selected as the study objects. The patients were randomly divided into control group and observation group, with 52 cases in each group. The control group was treated with allylestradiol tablets. Observation group was treated with Zishen Yutong pill on the basis of control group. The therapeutic effects, TCM syndrome scores, serum hormone levels [estradiol (E2), β-human chorionic gonadotropin (β-HCG), progesterone (P)], uterine hemodynamic indexes [systolic S-wave velocity to diastolic D-wave ratio (S/D), uterine artery flow resistance index (RI), pulsation index (PI)] of the two groups were analyzed and compared. Results The total effective rate of observation group was significantly higher than that of control group (P < 0.05). After 7 days of treatment, the TCM syndrome scores of the main disease, secondary disease and total score of the two groups were significantly decreased compared with 1 day before treatment, and compared with the control group, the TCM syndrome scores of the observation group were significantly decreased after 7 days of treatment (P < 0.05). After 7 days of treatment, the levels of E2 and P in both groups were significantly higher than those on 1 day before treatment, and the levels of β-HCG in both groups were significantly increased, and the improvement range of β-HCG, E2 and P in observation group was significantly greater than that in control group (P < 0.05). After 7 days of treatment, PI, RI and S/D in both groups were significantly decreased compared with 1 day before treatment, and PI, RI and S/D in the observation group were significantly lower than those in the control group (P < 0.05). Conclusion Zishen Yutong Pill combined with allylestradiol tablets can improve the therapeutic effect of TA, relieve disease symptoms, improve uterine hemodynamics and regulate serum hormone levels.