Chest and knee position is used to correct fetal malposition after pregnancy, and the best time is 30 weeks of gestation. However, the knee-chest position is not advocated nowadays, mainly because the fetal malposition itself indicates intrauterine abnormalities, such as cord winding or uterine malformation, and performing knee-chest position may increase the risk of fetal distress and fetal death in utero. Before 28 weeks of gestation, because the fetus is still small, the amniotic fluid is relatively large, and the fetus is more mobile, most of the breech first dew can be changed to head first dew by itself, so no correction is needed. If the fetal position is not corrected around 30 weeks of gestation, it will lead to the inability to deliver the baby smoothly. It is recommended to correct the fetal position by chest and knee position under the guidance of obstetrician, usually 2-3 times a day for 15 minutes each time, and to review the ultrasound at the obstetrics department after 1 week. Therefore, pregnant women should go to the hospital for prenatal checkups after pregnancy in order to detect problems such as fetal malposition in time.