What are the causes of intrauterine bleeding in early pregnancy?

1. Lack of progesterone. During early pregnancy, the ovaries form the corpus luteum to maintain nutritional supply. After three months, the placenta gradually forms, rendering the corpus luteum unnecessary. However, when the placenta has not yet formed, progesterone deficiency and bleeding can easily occur. Pregnant women need to supplement more natural progesterone.

2. Ectopic pregnancy. Ectopic pregnancy refers to the implantation of the embryonic sac outside the uterus instead of inside. Implantation outside the uterus prevents the embryo from growing normally, altering the ratio of estrogen and progesterone in the body, leading to decidual separation and subsequent bleeding. If ectopic pregnancy occurs, it is best to address it immediately, as the risk increases as the embryo grows. Some people even die from ruptured ectopic pregnancies and heavy bleeding.

3. Cervical diseases. In early pregnancy, bleeding can also originate from cervical issues besides embryonic factors. Severe cervical inflammation causes erosion, or cervical polyps present before pregnancy may lead to surface capillary rupture and bleeding due to hormonal changes during pregnancy. Regular cervical examinations should be conducted before pregnancy to prevent cervical issues from causing vaginal bleeding during pregnancy.

4. Spontaneous abortion. If the embryo has defects and stops developing after a period, a miscarriage will occur. Spontaneous abortion is inevitable. If this happens, medical intervention is necessary to clear residual tissue from the uterine cavity.

5. External factors. During early pregnancy, external factors such as heavy lifting, stress, and sexual activity can cause minor vaginal bleeding. It is advisable to rest in bed in such cases.