Fetal hypoxia may occur at 22 weeks. The 22nd week of pregnancy is the middle stage of pregnancy, at this time the intrauterine amniotic fluid volume is sufficient, the fetus in the uterus range of motion is relatively large, the fetus in the process of activity may cause the umbilical cord to be wrapped around the neck, the umbilical cord is too short or wrapped around the umbilical cord is too tightly may cause the fetus to be hypoxic. Placental infection or infarct foci, fetal developmental abnormalities, maternal gestational diabetes mellitus or gestational hypertension, causing the umbilical artery resistance to increase, can also cause fetal hypoxia, and in severe cases, may lead to intrauterine fetal death. 22 weeks of pregnancy usually have to do a good pregnancy obstetric examination, but also be able to find out whether the fetus in the uterus have hypoxia.