Treatment of Iron Deficiency Anaemmia in Pregnancy Study. The Clinical Impact of Treatment for Iron Deficiency Anaemia using an Optimized Care Pathway in accordance with national guidelines

Abstract

Abstract Iron deficiency anaemia is a common disorder affecting up to 30% of pregnant women. Treatment guidelines for iron deficiency anaemia in pregnancy exist, which if adopted, can reduce the associated risks of maternal and fetal morbidity and mortality. Objective: To optimise the implementation of the British Society of Haematology (BSH) guidelines, for the treatment of iron deficiency anaemia (IDA) in pregnancy, assessing response rates and predictability of response. Study population: A prospective cohort study of pregnant women with IDA at a single site. Methods: Women with anaemia were offered follow-up through a dedicated anaemia clinic. First line treatment was with ferrous sulphate 200mg three time a day as per earlier BSH guidelines. The response was assessed 2 to 4 weeks later by measuring the haemoglobin (Hb) concentration. A response was defined in 2 ways; i) a haematological response (HRes), a 10g/L increase in Hb and ii) adjusted obstetric response (ORes), a 10g/L increase in Hb and/or gestationally adjusted normalisation of the Hb. Education and advice were provided to women, with on-going follow-up at clinic appointments including an assessment of side effects. Continuing non-response led to an offer of intravenous iron infusion (IVI). Following a response with oral iron, treatment was continued for a further 3 months when the women were again reviewed. Results: The initial rate of HRes to a first course of oral iron was 36.5% and for ORES at 55.2%. At the end of all follow up, post-delivery, the HRes rate was 70.5% and ORes 88.5% (excluding 9 women lost to follow up). Responders (HRes) to oral iron had lower median Hb at diagnosis 95g/L compared to non-responders 100g/L. The responders median Hb was 113g/l versus 103g/L for non-responders at first follow-up and was Hb 122g/L versus 110 g/L, respectively, at the end of the study. The same pattern was seen for ORes. Non-responders reported more side effects than responders 15% versus 5% respectively. Logistic modelling suggested Hb at diagnosis, ethnicity, trimester at recruitment, marital status and parity had a predictive accuracy for a response of 75%. The specificity was high 89.8% but sensitivity low 42.9%. Conclusion: Oral iron treatment for IDA in pregnancy is challenging to deliver due to side effects and poor adherence, despite national guidelines. High rates of non-response were seen even in the setting of a specialist anaemia clinic. Alternative strategies such as prevention of IDA need to be evaluated.