Every other week ultrasound examination of the child has become smaller may be related to the deviation of ultrasound, unbalanced nutritional intake, pathology and other reasons. 1. Ultrasound deviation: Ultrasound is a kind of imaging examination, different doctors measure at different times, the position of the fetus in different positions may affect the results of the measurement, if the difference in value is not large, generally considered as a measurement error. 2. Unbalanced nutritional intake: Pregnant women may suffer from vomiting during pregnancy, resulting in insufficient nutritional intake and a small child. Pregnant women should take more nutritional supplements and eat more foods rich in protein as well as iron and calcium. 3. Pathological: If the function of the placenta is not good, it will cause unfavorable absorption of the fetus, resulting in developmental delay and small fetus. You need to seek immediate medical attention and further treatment under the guidance of the doctor. The next week ultrasound examination of the child has become smaller need to consult the obstetrician, under the guidance of the doctor to analyze the reasons for the treatment of the cause. The most important thing is to pay attention to the diet, nutritional balance, regular routine, maintain sufficient sleep; appropriate exercise, work and rest, keep the mood of the comfortable.