22 weeks fetal nasal bone not shown if it is caused by delayed development of nasal bone, it will grow later, but if it is caused by Down syndrome, it will not grow later. Nasal bone not shown in 22 weeks fetus during ultrasound examination is considered to be caused by delayed development of fetal bones, after a period of time the nasal bone will still grow, it is recommended that the pregnant woman should be examined again after 32 weeks. There is also a possibility that the fetus itself already has a nasal bone, but during the examination the fetal position does not cooperate, or the fetal nasal bone is blocked by the uterine cavity, there may also be a phenomenon that does not show the phenomenon of the nasal bone, this is not an abnormal situation, so the fetal nasal bone will continue to develop, it is recommended that pregnant women in the examination of the appropriate activities before the position of the fetus, to correct the position of the fetus. When a 22-week fetus undergoes ultrasound that does not show the nasal bone, it may be caused by pediatric Down syndrome, and the fetus will show symptoms such as organ hypoplasia, growth retardation, and nasal bridge hypoplasia. In this case, the nasal bone usually does not grow back, and the pregnant woman is advised to undergo amniocentesis to determine the exact cause. If the ultrasound examination of the fetus at 22 weeks does not show the nasal bone, the pregnant woman is advised to repeat the examination on time and undergo amniocentesis if necessary.