The burden of anaemia remains unacceptably high during pregnancy. Over a third of women are anaemic by their third trimester of pregnancy. The most common cause is iron deficiency. One key factor is rising iron requirements throughout pregnancy. There are risks associated with anaemia for the mother and infant. Anaemia in the first and second trimester has been significantly correlated with low birth weight and pre-term birth, and is associated with impaired neurological development of the baby. It also increases the risk of intrauterine fetal death, and the likelihood of the mother requiring blood transfusions during or after delivery.This study is a prospective cohort study, which aims to better define the natural history and understand how to use oral iron therapy for iron deficiency anaemia in pregnant women. This includes documenting the impact of treatment on anaemia symptoms, side effects, and the level of success of iron therapy using several haematological tests. Pregnant women will be invited to participate in this study and treated using a treatment schedule as described in national guidelines. Additional blood samples will be taken for subsequent detailed analysis of pathways of iron metabolism to better predict the response to oral iron therapy during pregnancy.

Inclusion Criteria:

• Pregnant women (any stage during pregnancy up to 36 weeks) and women in the puerperium (within 6 weeks postdelivery) with anaemia as defined by World Health Organization (WHO) criteria and described in British Society Haematology (BSH)/ British Committee for standards in Haematology (BCSH) guidelines.

  1. First trimester < 110g/l
  2. Second and third trimester < 105g/l
  3. Puerperium < 100g/l

• Age: 18-45 years

• Agreement to participate in the study with consenting

Exclusion Criteria:

• Anaemic women presenting at or after 36 weeks as there may be insufficient time to delivery to assess responses to oral iron)
• Anaemic women affected by a (major) haemoglobinopathy e.g. B thalassaemia major sickle cell disease
• Women with overt clinical signs of sepsis
• Allergies to iron
• Hyperemesis Gravidarum / persistent vomiting
• Women with inflammatory conditions such as Crohns, ulcerative colitis, Systemic lupus erythematosus, Rheumatoid arthritis.
• Women with chronic renal failure

Anaemic (iron-deficient) pregnant women.

Anaemic (iron-deficient) pregnant women receiving oral iron replacement therapy.