High serum ferritin in pregnant women may be caused by conditions such as folic acid supplementation, iron deficiency anemia, and abnormal liver function. 1. Supplementation of folic acid: it is possible for pregnant women to have high serum ferritin if they take excessive folic acid supplementation during pregnancy. 2. Iron deficiency anemia: when pregnant women have iron deficiency anemia, the concentration of iron ions in the blood will decrease, and serum ferritin will increase because of the lack of combination with iron ions. 3. Liver function abnormality: when pregnant women suffer from acute hepatitis, liver failure and other liver function damage, it will lead to liver function abnormality and serum ferritin decay. Pregnant women during pregnancy should pay attention to more nutrition, pay attention to diet and nutritional balance. Regular checkups, if at any time there is abdominal pain or abnormal vaginal bleeding and other special discomfort need to consult a doctor as soon as possible.