Anaemia is caused by low haemoglobin levels (Hb) in the blood.
Newborns often have high Hb levels when they are born. Hb levels will fall naturally. Premature babies are immature and their bone marrow will not start to produce new blood in the same way as in full-term babies, and they often require repeated blood tests. This leads to many premature babies developing anaemia and they may need one or several blood transfusions.
Newborns have a total blood volume of around 85ml per kilo, i.e. less than ten centilitres if they weigh 1 kilogram.
Text: Kajsa Bohlin Blennow