Whether the bleeding is from cervical polyps or placenta previa can be determined by gynecological examination and ultrasound. But no matter which kind of bleeding is pathological bleeding. 1. Bleeding from cervical polyps: during gynecological examination, there are superfluous organisms in the cervix, and the blood in the vagina comes from the cervical polyps rather than from the cervical opening, which may aggravate the bleeding after sexual intercourse or gynecological examination, and the ultrasound shows that the placenta is in a normal position. 2. Placenta hyperemesis gravidarum: It means that the placenta is in a low position, close to or covering the endocervical os, and the bleeding is caused by the misalignment of the placenta membrana at the endocervical os with the wall of the uterus, which is often manifested as painless vaginal bleeding. Ultrasonography shows that the placenta is lower and reaches or covers the endocervical os, and there is no bulky organisms in the cervix on gynecological examination, and blood flows out of the cervical os from the vagina. Both of the above cases belong to pathologic bleeding, so patients who have vaginal bleeding should consult a doctor promptly. During pregnancy, patients should pay attention to resting more, relaxing, avoiding tension and anxiety, and should go to the hospital in time if there is any discomfort, so that the doctor can make a clear diagnosis and cooperate with the doctor to deal with the symptoms.