If a pregnant woman experiences hypoxia, moderate oxygen intake is beneficial to the fetus, but excessive oxygen intake may have adverse effects on the fetus. Pregnant women and embryonic tissues do not need oxygen if there are no symptoms of hypoxia during pregnancy. If the fetal tissues and the pregnant woman show symptoms of hypoxia, such as weak fetal movements and slow or rapid fetal heart rate, the pregnant woman is in need of oxygen. Moderate oxygen intake is beneficial to the fetus and has no adverse effects on embryonic development. Hypoxia may occur in the middle and late stages of pregnancy, and low concentration and low frequency intermittent oxygen intake can prevent intrauterine distress and reduce the incidence of neonatal asphyxia. However, it is necessary to avoid over-oxygenation, which may lead to placental vasoconstriction and aggravate fetal hypoxia. In clinical practice, pregnant women with hypoxia should take moderate oxygen under professional doctor’s guidance, avoiding self-operation or over-oxygenation that may cause harm to the fetus.