Bleeding similar to menstruation in early pregnancy is mainly related to fertilized egg implantation, pre-eclampsia, ectopic pregnancy and embryonic abortion, the details are as follows: 1. fertilized egg implantation: implantation bleeding occurs in early pregnancy due to fertilized egg implantation and stimulation of the endometrial wall, usually accompanied by a feeling of vague pain in the small abdomen, the symptoms are mild and usually do not affect the development of the fertilized egg, which will be relieved by itself in about 2 days; 2. Premature miscarriage: The fetus is relatively unstable in early pregnancy and belongs to the peak of miscarriage. If a pregnant woman has vaginal bleeding, bright red or dark red, accompanied by strong pain in the lower abdomen, falling sensation, back pain and other symptoms, it is recommended to have an ultrasound examination in time, and if the fetus is developing normally, progesterone and other drugs can be given under the guidance of the doctor for fetal preservation treatment, while closely observing the changes in the amount of bleeding. If the embryo is poorly developed, treatment can be carried out to remove the uterus. 3. Ectopic pregnancy: it usually manifests as irregular vaginal bleeding with dark red color, small amount and incomplete dripping, and when the ectopic pregnancy ruptures, it will suddenly feel tearing pain in one side of the lower abdomen, often accompanied by nausea, vomiting and a feeling of falling abdomen. If you have a ruptured ectopic pregnancy, you will feel a sudden tearing pain in one side of your lower abdomen, often accompanied by nausea, vomiting and a feeling of swelling in the abdomen. You should go to the hospital as soon as possible to check the development of the embryo in the uterus and terminate the pregnancy in time after confirming fetal arrest.