Objective To investigate common causes of anemia of premature infants and its related factors. Methods Medical data of 60 premature infants with anemia( observation group) admitted to our hospital from June,2013 to June,2014 were analyzed retrospectively,and the common causes were analyzed. 60 premature infants without anemia in the same period were selected as control group. Then,birth weight,gestational age,average hospitalization hemoglobin( Hb) as well as history of hypoxia in infants,history of anemia ...