The most dangerous symptom from eight to ten weeks of pregnancy is vaginal bleeding. This is because this is the time when the placenta and the ovarian corpus luteum work against each other, that is, before the tenth week of pregnancy, the estrogen and progesterone in the body are secreted by the corpus luteum, and when the corpus luteum starts to shrink after the tenth week, the placenta starts to secrete estrogen and progesterone to maintain the growth of the fetus. At this time, if the articulation is not good, there is a risk of vaginal bleeding and preterm miscarriage. If there is more bleeding, it may cause unavoidable miscarriage. Therefore, if a small amount of vaginal bleeding occurs at this time, it is important to go to the hospital promptly for examination and then for treatment to preserve the fetus.