Anaemia is defined as haemoglobin concentration in blood below the lower limit of the normal range for the age and sex of the individual. In adults, the lower extreme of the normal haemoglobin is taken as 13 g% for males and 11.5% for females. New born infants have higher haemoglobin levels and therefore, 15% is taken as the lower limit at birth, whereas at 3 months, the lower limit is taken as 9.5%. Although haemoglobin value is employed as the only parameter for determining whether or not anaemia is present, the red cell counts, haematocrit(PCV) and absolute values (MCV, MCH and MCHC) provide alternate means of assessing anaemia.

The symptoms of anaemia are: