NT is the fetal nuchal translucency band, the upper lip may not show up clearly by NT examination at 12 weeks of pregnancy may be caused by factors such as shorter pregnancy time and fetal position obscuring. Pregnancy 12 fetus development is still relatively small, the upper lip is not yet complete development, through the NT examination may not show clear. You can do four-dimensional ultrasound in 22-26 weeks of pregnancy, if the examination of the upper lip does not show clear, you need to consider the possibility of cleft lip and palate. In addition, 12 weeks pregnant NT examination shows that the upper lip is not clear, may also be examined by the fetal position, due to the abdominal wall fat and uterus to affect the doctor’s line of sight, also can not see the upper lip of the fetus, which does not mean that the upper lip of the fetus has not grown well. Generally, you should go to the hospital for NT test at 11-13+6 weeks of pregnancy, and if the test result is abnormal, you can further do non-invasive DNA and amniocentesis screening.