Fetal position RSA is breech position, R is right, S is sacral, A is anterior, mainly refers to the fetal sacrum is located in front of the right side of the pelvis, also called right sacral anterior position, which is an abnormal fetal position. When the fetal position is RSA, the fetus faces the cervical opening with its buttocks, which cannot completely block the cervical opening because of the small size of the fetus’ buttocks. When the water breaks, the umbilical cord will easily slip out from the gap, causing the cord to prolapse, and if the delivery is not finished within 8 minutes after the umbilical cord is delivered, it will make the umbilical cord squeezed for too long, which may lead to the death of the fetus. the RSA fetal position can usually be changed to head position before 34 weeks of pregnancy, and after ultrasound examination, if there are no symptoms such as umbilical cord around the neck, abdominal pain, vaginal bleeding, and the placenta position is normal, you can perform knee-chest The fetal position can be corrected by lying down. After 32-34 weeks of pregnancy, the fetal position is relatively fixed. If the fetal position is still breech, it is difficult to change to head position, so it is recommended to perform cesarean section.