Oral Iron Supplementation in Pregnancy

Initial Screening and Diagnosis

The Centers for Disease Control and Prevention recommends screening all pregnant women for anemia at the first prenatal visit using hemoglobin or hematocrit measurements, with anemia in the first trimester defined as hemoglobin <11.0 g/dL 2
A presumptive diagnosis of iron deficiency anemia can be made if the patient is not acutely ill, and treatment should begin immediately without waiting for confirmatory testing, as suggested by the Centers for Disease Control and Prevention 2
The European Society for Gastrointestinal Endoscopy recommends performing coeliac serology as part of the evaluation, particularly if there is a family history of gastrointestinal neoplasia or coeliac disease 1

The American College of Obstetricians and Gynecologists recommends prescribing oral iron at 60-120 mg/day of elemental iron as first-line treatment 2
The American Gastroenterological Association suggests that taking iron with ascorbic acid (vitamin C) enhances absorption, though evidence supporting this practice is limited 4

The Academy of Nutrition and Dietetics recommends counseling patients about consuming iron-rich foods including meat, poultry, certain fruits and vegetables, and iron-fortified grain products 2
The American Gastroenterological Association advises patients that taking iron with food or using enteric-coated formulations may improve tolerability but will decrease absorption 4

The Centers for Disease Control and Prevention recommends reassessing hemoglobin after 4 weeks of treatment, expecting an increase of ≥1 g/dL or hematocrit increase of ≥3% 2
The American College of Obstetricians and Gynecologists suggests that if no response occurs after 4 weeks despite confirmed compliance and absence of acute illness, perform additional testing including mean corpuscular volume (MCV), red cell distribution width (RDW), and serum ferritin 2

The American College of Obstetricians and Gynecologists recommends referring to a physician familiar with anemia in pregnancy if hemoglobin is <9.0 g/dL or hematocrit is <27.0% 2
The American College of Obstetricians and Gynecologists suggests switching to intravenous iron if the patient fails oral therapy after 4 weeks, cannot tolerate oral preparations, or requires rapid correction of anemia 5

The European Society for Gastrointestinal Endoscopy states that there is no evidence that oral iron supplementation in the first trimester causes harm to mother or fetus 1
The European Society for Gastrointestinal Endoscopy recommends that upper gastrointestinal endoscopy and duodenal biopsy can be performed safely in pregnancy if coeliac disease is suspected, as there is no evidence this is unsafe 1

The European Society for Gastrointestinal Endoscopy recommends not attributing iron deficiency anemia to aspirin, warfarin, or proton pump inhibitors without completing appropriate investigations, as these medications do not reduce the likelihood of underlying gastrointestinal pathology 1
The American College of Obstetricians and Gynecologists suggests not assuming compliance—verify that patients are actually taking the medication, as side effects frequently lead to discontinuation 5