Anticoagulation during menstruation Most people do not have much menstruation, and the amount of anticoagulants used remains unchanged If bleeding increases, the amount of warfarin can be reduced If bleeding is heavy, vitamin K1 can be injected to stop bleeding If menstrual disorders occur and bleeding continues, menstrual medication should be taken to regulate menstruation Sun Zongquan, Department of Cardiac Surgery, PUMC Hospital Wuhan A very small number of large amounts of bleeding, hysterectomy is required Anticoagulation during pregnancy Warfarin can enter the placenta, and the risk of fetal abnormalities in the first trimester is associated with the administration of warfarin. Warfarin can enter the placenta, and taking warfarin in the first trimester of pregnancy may cause fetal malformations. Heparin cannot cross the placenta, stop warfarin in the first trimester and inject heparin subcutaneously. If the pregnancy is not suitable for continuation, abortion is feasible. Anticoagulation in the perinatal period: change warfarin to heparin 1-2 weeks before the expected date of delivery; use ichthyoglobulin to counteract bleeding in the postpartum period; start taking warfarin orally again if there is no bleeding 24-48 hours after delivery of the fetus. If warfarin is not stopped, inject vitamin K1 after contractions start, and restart warfarin if there is no bleeding sign 24-48 hours after delivery of the fetus. Cesarean section surgery: anticoagulation should be discontinued for elective surgery; if emergency surgery is needed, blood should be collected immediately to measure the prothrombin time and activity, and at the same time, vitamin K1 20mg should be injected staticly, and surgery can be performed after 4 hours of rechecking the prothrombin time is normal; if the time is urgent, the surgery can be performed without waiting for the results of the laboratory tests, and then start the surgery after injecting vitamin K1, and then the hemorrhage can be carefully stopped during the surgery, and then the anticoagulation can be restarted after bleeding stops in 24-48 hours.