Iron deficiency is thought to be the most common nutrient deficiency among pregnant women and the most common cause of anemia in pregnancy. The consequences of iron deficiency anemia are serious and can include diminished intellectual and productive capacity and possibly increased susceptibility to infection in mothers and infants, low birthweight, and premature births, hence the importance of appropriate treatment during pregnancy.

Most guidelines recommend an increase in iron consumption by about 15-30 mg/day, an amount readily met by most prenatal vitamin formulations. This is adequate supplementation for non-anemic and non-iron-deficient women. However, women with iron deficiency anemia should receive an additional 30-20 mg/day until the anemia is corrected.

It is not clear whether intermittent administration of oral iron is equivalent to once daily to rise the hemoglobin levels in pregnant women with iron deficiency anemia. Alternate day treatment with supplemental iron has been suggested as a way to improve its absorption because daily doses may suppress the mucosal uptake of iron even in the presence of iron deficiency until the intestinal mucosa completes its turnover.

Another possible factor associated with the frequency of iron dosing is related to hepcidin, the central regulatory molecule in the metabolism of iron in mammals. The synthesis of hepcidin is controlled by 3 kinds of signals: inflammation; the need for increased erythropoiesis, and an iron status signal based on plasma iron levels and iron stores. If plasma iron levels or iron stores are increased, the resulting signal increases hepcidin levels, thereby blocking iron absorption and its release from stores (liver, macrophages) and preventing iron overload.This hepcidin effect, suppressing iron absorption, could last as long as 48h.

In this study, the researchers aim to determine if alternate day dosing of iron in pregnant women with iron deficiency anemia results in improved levels of hemoglobin or hematocrit and ferritin.

Hepcidin levels will be compared between patients on daily iron supplementation versus alternate day supplementation.

The researchers will also evaluate if alternate day dosing of iron supplementation results in a better side effect profile, and with better patient compliance.

Inclusion Criteria:

• Pregnant patients with iron deficiency anemia, defined as Hb less than 11.0 or hematocrit less than 33% with ferritin 25 ug/L
• Age 18-64 years old.
• Gestational age between 12 0/7 weeks and 34 0/7 weeks.
• No other known causes of anemia (Folate or vit b12 deficiency anemia, sideroblastic anemia, thalassemia, sickle cell anemia, aplastic anemia, hemolytic anemia, anemia of chronic disease). Anemic patients with a low ferritin level and a mean corpuscular volume (MCV) >95 will have folate and vitamin B12 measured since some patients might have combined causes of anemia and might not respond as expected to iron supplementation only.

Patients will also be required to have a normal HB electrophoresis; this is a routine test obtained on all prenatal patients.

Exclusion Criteria:

• Patients currently receiving iron supplementation
• Malabsorptive and restrictive bariatric surgery
• Inflammatory bowel disease
• Irritable bowel syndrome
• Celiac disease/atrophic gastritis/Helicobacter pylori
• Active infection (ferritin can be falsely elevated since apoferritin is an acute-phase protein like CRP and increases both during infections and inflammatory reactions eg postoperatively).
• Patients with contraindications to iron supplementation such as iron overload or hypersensitivity

Female