31 weeks of pregnancy fetal double ear display is not clear may be the fetal position influence or missing caused, according to the specific situation corresponding treatment. 31 weeks of pregnancy belongs to the late stage of pregnancy, due to the growth of the fetus, the position in the uterine cavity is relatively small, was flexed and curled up state, do ultrasound due to the influence of the position of the obscured parts of the invisible or unclear, is normal, can be appropriate after the activities or after the ultrasound again, generally do not need special treatment. However, if the two ears are still not clearly visible after 4D ultrasound examination or several times of rechecking, it is likely to be caused by the lack of, need to improve the examination to determine whether there is chromosomal abnormality caused by, such as malformations, if the problem is serious, the need to terminate the pregnancy. Pregnant women are advised to have regular checkups and follow the doctor’s instructions for checkups and treatments.