Objective: To study on the action mechanism of benefiting Qi and dissipating blood stasis for treating uterine abnormal hemorrhage for copper intrauterine device(Cu-IUD). Methods: Contrasted with pregnendione and oxytocin, it was observed that the effect of 98-B with the principle of benefiting Qi and dissipating blood on the contraction of uterus smooth muscle, in rats by LMS physiological recorder and JH-2 muscle strain sensor. Results: 98-B has different intensifying action, but it has distinct counterwork to uterine contraction. Conclusion: 98-B has bi-directional accommodation action to t...