SD value is the ratio of fetal umbilical artery systolic pressure to diastolic pressure, which is used to determine the blood supply to the fetus. SD value will be abnormal when the placenta is malfunctioning or the umbilical cord is abnormal, so it is best to go to the hospital for regular checkups, and abnormalities need to be reasonably regulated. If the SD value increases, it may be caused by intrauterine hypoxia of the fetus, and it is necessary to go to the hospital for further examination in time, so that the fetal heart can be tested and the baby’s development can be observed. Reasonable oxygen intake under the guidance of a doctor can prevent fetal hypoxia, serious hypoxia can easily affect the baby’s development causing intrauterine asphyxia, if necessary, timely go to the hospital for caesarean section, can prevent hypoxia, it is best not to exercise strenuously during pregnancy.