This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaemia in Pregnancy, Subject name: Gynaecology & Obstetrics
Which amongst the following is the indication for parenteral iron therapy? 
Select and explain. 
A. Compliant patient, B. Intolerance to oral iron, C. When an immediate rise of Hb is required such as a patient in labour, D. To decrease the duration of oral medication
B: Intolerance to oral iron
Answer: B: Intolerance to oral iron 
Explanation: Indications of parenteral iron therapy: 1. Oral therapy is contraindicated 2. Patient is non compliant to take oral iron 3. Non-tolerance to oral iron 3. Malabsorption Syndrome. 4. Moderate anemia in third trimester NOTE: the rate of increase of Hb is almost same as that with oral iron therpy. Therefore in any condition where quick Hb build up is required, blood transfusion should be considered.