It is possible for a placenta previa to grow back in the later stages of the state, and it depends on each individual as to whether or not it will eventually grow back. If the placenta is already covering the cervical opening at the time of the examination, the chances of it growing back up are very small, and if it is still some distance away from the cervical opening, the chances of it growing back up will be higher. At the mid-pregnancy checkup the placenta is low and if it is directly over the cervical opening, the chances of it growing back up afterwards are low. If it does not cover the cervical opening, the lower part of the uterus is pulled and stretched to a great extent as the weeks of pregnancy increase and the fetus grows. The placenta, on the other hand, is attached to the lower segment of the uterus and gradually moves away from the cervical opening as the lower segment of the uterus stretches. However, if the lower edge of the placenta reaches or covers the cervical opening on ultrasound after 28 weeks of pregnancy, placenta praevia is diagnosed. Placenta praevia is a common cause of vaginal bleeding in late pregnancy. If you are diagnosed with placenta praevia, you need to stay in bed more often and seek medical attention when bleeding symptoms occur.