Baby 6 months medical checkup will generally check fasting blood glucose and liver function, blood sampling is definitely required fasting, if eating on liver function and blood glucose will have a certain impact on the results are not normal, it is difficult to analyze the cause of the disease. But 6 months old babies because of their young age can not tolerate a long fasting, may cause hypoglycemic episodes affect physical and mental health, the general adult blood draw fasting requirements of 6-8 hours or more, 6 months old babies generally require at least 2-3 hours or more, the impact on the medical examination blood draw down to a lower level is possible. In addition to fasting for blood draws, fasting is also required for routine abdominal color ultrasound examinations, because eating can also affect the analysis of ultrasound results.