Subjects were tested for hemoglobin, ferritin, serum iron, transferrin saturation and reticulocyte count during routine prenatal examination at 24-26 weeks of gestation, and blood samples were taken for serum hepcidin detection in the laboratory and the values were recorded. Those who met the criteria were included in the study group, signed the informed consent form and randomized into groups, and were given different drug administration schemes (150mg orally every day, 300mg orally every day, 150mg orally every other day, 300mg orally every other day, intravenous). At the same time, each subject was given anemia diet education, and all subjects were given folic acid 400ug/d and vitamin C 0.5g/d orally during the treatment period. If the subjects were in the oral iron group, the same time of oral iron was determined as 20 o'clock ± 1 hour in the evening, and the oral iron was not taken with other drugs; If the subject is in the intravenous medication group, the medication is scheduled to be administered at a uniform time of 8 o'clock ± 1 hour in the morning. The above subjects were followed up. Hemoglobin, ferritin, serum iron, transferrin saturation and reticulocyte count were performed at 30-32 and 37 weeks of pregnancy and delivery, and blood samples were taken for serum hepcidin detection in the laboratory and the values were recorded. The adverse reactions were investigated with a questionnaire at the last prenatal examination before delivery. After full term delivery, the patient fills in the delivery information and enters it into the database. Finally, the data statistician and the above personnel used the blind method for statistical analysis and reached a conclusion.

Subjects were tested for hemoglobin, ferritin, serum iron, transferrin saturation and reticulocyte count during routine prenatal examination at 24-26 weeks of gestation, and blood samples were taken for serum hepcidin detection in the laboratory and the values were recorded. Those who met the criteria were included in the study group, signed the informed consent form and randomized into groups, and were given different drug administration schemes (150mg orally every day, 300mg orally every day, 150mg orally every other day, 300mg orally every other day, intravenous). At the same time, each subject was given anemia diet education, and all subjects were given folic acid 400ug/d and vitamin C 0.5g/d orally during the treatment period. If the subjects were in the oral iron group, the same time of oral iron was determined as 20 o'clock ± 1 hour in the evening, and the oral iron was not taken with other drugs; If the subject is in the intravenous medication group, the medication is scheduled to be administered at a uniform time of 8 o'clock ± 1 hour in the morning. The above subjects were followed up. Hemoglobin, ferritin, serum iron, transferrin saturation and reticulocyte count were performed at 30-32 and 37 weeks of pregnancy and delivery, and blood samples were taken for serum hepcidin detection in the laboratory and the values were recorded. The adverse reactions were investigated with a questionnaire at the last prenatal examination before delivery. After full term delivery, the patient fills in the delivery information and enters it into the database. Finally, the data statistician and the above personnel used the blind method for statistical analysis and reached a conclusion.

1.1 Oral iron：NIFEREX®（Each granule contains 0.15g of polysaccharide iron complex ，Kremers Urban Pharmaceuticals Inc.

） 1.2 Daily iron supplement scheme (QD)：Oral polysaccharide iron complex capsule 150mg/300mg daily.

1.3 Alternative iron supplement scheme（QOD）：）Oral polysaccharide iron complex capsule 150mg/300mg every other day 2.1Intravenous iron supplement：Iron Isomaltoside Injection（5ml： 500mg，Wasserburger Arzneimittelwerk GmbH）,Intravenous iron supplement

Inclusion Criteria:

• The patient was examined and delivered at the First Affiliated Hospital of Shandong First Medical University (Qianfo Mountain Hospital of Shandong Province)
• Clinical diagnosis of ID（iron depletion）
• Clinical diagnosis of IDA（iron depletion anemia）
• In the second trimester of pregnancy (24-26 weeks of pregnancy)
• Must be able to swallow tablets
• Agree to participate in the trial and sign the informed consent.

Exclusion Criteria:

• C-reactive protein in serum ≥5mg/L；
• Clinical diagnosis of Hypertensive disorders complicating pregnancy
• Clinical diagnosis of Gestational diabetes
• Clinical diagnosis of Hypothyroidism
• Clinical diagnosis of Chronic digestive system diseases
• Clinical diagnosis of Renal insufficiency
• Clinical diagnosis of psychiatric diseases
• Clinical diagnosis of fetal growth restriction
• Clinical diagnosis of placenta previa
• Clinical diagnosis of placental abruption
• Clinical diagnosis of fetal distress
• Clinical diagnosis of premature rupture of membranes
• Clinical diagnosis of Thalassemia
• Clinical diagnosis of Hemoglobinopathy
• Use anticoagulant drugs for treatment
• Smoking
• Excessive drinking
• Clinical diagnosis of Hemorrhoids
• Take acid inhibitor

Women of childbearing age who can be pregnant