Vaginal bleeding in the second trimester of pregnancy is often related to the following factors:1. It is caused by the lack of embryonic genes, which often fails even if the treatment is anabolic.2. Pregnant women who suffer from some kind of serious internal diseases, such as serious damage to liver function and kidney function, can also lead to the occurrence of vaginal bleeding in the early stage of pregnancy in the clinic.3. Sudden stimulation due to noise can also lead to preeclampsia.4. Divorcing between the uterine wall and the gestational sac due to sexual intercourse, exertion or doing heavy physical labor can cause vaginal bleeding in the clinic. Therefore, if vaginal bleeding is found, it is recommended to have an ultrasound examination to first determine whether the fetus is in good condition. If the fetus is in good condition, it is recommended to arrange treatment positively.