Routine oxygen is not usually needed in late pregnancy. If there is maternal hypoxia or intrauterine fetal hypoxia, growth retardation or placental dysfunction, the best time to administer oxygen at this time is the sooner the better. In late pregnancy, if the fetus is in good condition and there is no abnormality in fetal movement and fetal heart monitoring, oxygen is not needed. If there is frequent fetal movement, decreased fetal movement, fast or slow fetal heart rate, the fetus may have intrauterine hypoxia, it is recommended to administer oxygen in time, usually for half an hour. If the concentration of oxygen is too high, it may lead to fetal retinopathy. In late pregnancy, if the fetus increases in size and presses on the diaphragm, pregnant women may feel difficulty in breathing, which can also be improved by low-flow oxygen intake if heart-related diseases are excluded. During pregnancy, you should have regular maternity checkups, count fetal movements every day, increase the time of outdoor activities appropriately, and avoid going to crowded places to avoid maternal and fetal hypoxia.