Anterior wall placenta generally can not become posterior wall placenta, no matter anterior wall placenta or posterior wall placenta is the normal position of the placenta, is no need to deliberately change. Normal placental position is located in the anterior or posterior wall of the uterus, or may be the anterior or posterior wall of the uterus, generally as long as it is not around the endocervical opening is a relatively normal position, generally the position of the placenta ultrasonography is correct in the later stage is not easy to change, with the increase of pregnancy weeks, the uterus gradually increase in size, there will be up and down changes. However, the anterior and posterior walls will not change, because the placenta is the initial location of the pregnant egg, with the increase in gestational weeks and ultimately developed into the placenta, this is fixed. If the anterior wall of the placenta becomes the posterior wall, it may be due to errors in the ultrasound examination or problems with the angle of the examination at different gestational weeks, in addition to ruling out placenta previa and placenta praevia abnormalities. It is recommended to have regular checkups during pregnancy, pay attention to the monitoring of the placenta and fetal heart rate, and go to the hospital promptly if you have abdominal pain, vaginal bleeding, or abnormal fetal movement during pregnancy.