[Medical Q&A] Why are there huge differences in the hemoglobin levels of newborns during multiple tests?

Planner: Chinese Medical Association

Reviewer: Ning Yongzhong, Chief Technician, Beijing Chuiyangliu Hospital

Newborns undergo routine examinations after birth, including multiple blood tests. If the hemoglobin levels in multiple tests vary greatly, the possible reasons include the following.

1. Physiological fluctuations: In the early days of a newborn, the baby's blood may be in a concentrated state; when blood is collected later, the newborn has already eaten and the blood may be diluted, so there will be normal physiological fluctuations. Literature shows that the results of blood cell analysis of newborns in different age groups (1-3 days, 4-7 days, 8-14 days, 15-21 days, 22-28 days) vary greatly, but most of them are physiological changes.

2. Sampling error: Differences in sampling operations, such as sampling locations and sampling times, may also cause changes in test results.

3. Sample processing: Errors in sample processing, such as insufficient mixing and improper storage conditions, may also affect the accuracy of the test results.

4. Instrument differences: When testing different batches or different instruments, there may be certain errors, especially when the instrument calibration is inconsistent.

5. Anemia: If the hemoglobin level of the newborn is continuously lower than the normal range, it may indicate anemia and further examination is needed to determine the specific cause, such as iron deficiency, hemolytic anemia, etc.

6. Blood transfusion or infusion: If the newborn receives a blood transfusion or a large amount of infusion, it may also affect the hemoglobin test results.

7. Other health problems: Certain health conditions, such as dehydration, infection, etc., may also cause fluctuations in the hemoglobin level of the newborn.

Therefore, if the results of multiple routine blood tests of newborns are inconsistent, parents do not need to be too nervous and should communicate with clinical physicians in a timely manner. Physicians will comprehensively analyze the causes based on the test process and clinical manifestations and identify physiological and pathological abnormalities.