A low lying placenta is dangerous throughout the pregnancy, but it is most dangerous after the twenty-eighth week of pregnancy and becomes more dangerous the further along you are. Until 28 weeks, there is still hope that the low lying placenta will grow upward and leave the low lying position to return to its normal position. However, if the placenta is not in a normal position after 28 weeks, it will form a true placenta previa, and the closer the placenta is to the uterine opening, the more dangerous it is. If you find painless vaginal bleeding, recurrent vaginal bleeding, and possibly a drop in blood pressure and a weak pulse, you should go to the hospital in time, as heavy bleeding can lead to hemorrhagic shock, fetal hypoxia, or even neonatal asphyxia and death. Therefore, if the placenta previa is still significant in late pregnancy, you should contact your doctor as soon as possible to evaluate the appropriate delivery method and make relevant interventions, such as promoting alveolar maturation, terminating the pregnancy in time to remove the baby, and so on.