Intravenous Iron Isomaltoside Versus Oral Iron Supplementation for Treatment of Iron Deficiency in Pregnancy.

Inclusion Criteria: 1. Women aged ≥18 years 2. Pregnancy at GA 14+0 - 19+0 3. Ferritin \<30 μg/L after 4 weeks of standard treatment in a clinical setting 4. Willingness to participate and attend all planned follow-up visits, and signing the in-formed consent form Exclusion Criteria: 1. History of anaemia caused by e.g. thalassemia, hypersplenism or haemolytic anaemia (known haematologic disorder other than iron deficiency) 2. Iron overload or disturbances in utilisation of iron (e.g. haemochromatosis and haemosiderosis) 3. Drug hypersensitivity (i.e. previous hypersensitivity to IV iron) 4. Known hypersensitivity to any excipients in the investigational drug products 5. History of active asthma within the last 5 years 6. History of multiple allergies 7. Known decompensated liver cirrhosis or active hepatitis 8. Active acute or chronic infections (assessed by clinical judgement) 9. Rheumatoid arthritis with symptoms or signs of active inflammation 10. Treated with IV iron products or blood transfusion within 4 weeks prior to inclusion 11. Treated with erythropoietin (EPO) within 4 weeks prior to inclusion 12. Participation in any other interventional trial where the trial drug has not passed 5 half-lives prior to inclusion 13. Any other medical condition that, in the opinion of the Investigator, may cause the subject to be unsuitable for the completion of the trial or place the subject at potential risk from being in the trial 14. Meeting RBC-transfusion criteria (Hb ≤6.9 g/dL= 4.3 mmol/L with intolerable symptoms of anaemia like severe palpitations, severe dizziness, shortness of breath at rest or syncope or an Hb ≤6.4 g/dL (4.0 mmol/L) without intolerable symptoms of anaemia) 15. Multiple pregnancies 16. Inability to read and understand the Danish language