after obtaining parental informed consent , laboratory tests of iron status were performed on venous blood and infants with hemoglobin level greater than 10.5 g/dl were randomly chosen to receive 1.2 ml of ferrous sulfate ( feso4 ) drops ( about 3 mg of iron per kilogram per day ) or equal volume of placebo for 3 months .
C0302583
iron
C0060282
ferrous sulfate