The aetiology of severe anaemia among antenatal patients of the Port Moresby General Hospital

Between October 1998 and September 2000, 111 consecutive pregnant patients admitted to the Port Moresby General Hospital antenatal ward with a haemoglobin level of 6 g/dl or less were studied. The main causes of the severe anaemia were as follows: iron deficiency on its own or in combination with another factor 66%--iron deficiency on its own 43% and combined folate and iron deficiency 23%--and folate deficiency 18%. Malaria was a contributory factor in 13 patients (12%). A combination of blood film, bone marrow study, serum assays of ferritin, folate and vitamin B12, and mean corpuscular volume (MCV) was used to determine the cause of the anaemia. Ferritin levels on their own poorly correlated with the presence of iron in the bone marrow. A low MCV correlated well with iron deficiency anaemia while a high MCV was associated with folic acid deficiency. It would seem therefore that while a bone marrow study is mandatory to reach a definitive diagnosis of severe anaemia, MCV, in conjunction with the red cell morphology on blood film, would be a good marker for iron and folic acid deficiency anaemia, especially as we do not have serum assays readily available for folate, ferritin and vitamin B12 in Papua New Guinea.