Treatment of Iron Deficiency Anemia at 14 Weeks Gestation
For a 14-week pregnant patient with hemoglobin 9.4 g/dL, start oral ferrous sulfate 60-120 mg of elemental iron daily as first-line therapy. 1
Initial Management Approach
Oral iron supplementation is the appropriate initial treatment for this patient. The hemoglobin of 9.4 g/dL represents mild anemia in pregnancy (defined as Hb 9.0-10.9 g/dL in the second trimester), and the Centers for Disease Control and Prevention recommends oral iron as first-line therapy for this severity level. 2, 1
Why Oral Iron is Correct
The American College of Obstetricians and Gynecologists recommends 60-120 mg of elemental iron daily for mild to moderate anemia in pregnancy. 1 This is typically achieved with ferrous sulfate 325 mg once or twice daily, as each 325 mg tablet contains 65 mg of elemental iron. 3
In non-acutely ill pregnant women, make a presumptive diagnosis of iron deficiency anemia and begin treatment immediately without waiting for additional testing. 1 At 14 weeks gestation with Hb 9.4 g/dL, this patient fits this clinical scenario perfectly.
Confirm the positive screening with a repeat hemoglobin or hematocrit before initiating treatment. 2, 1 However, if already confirmed, proceed directly to treatment.
Why Blood Transfusion is Incorrect
Blood transfusion is not indicated for hemoglobin 9.4 g/dL. The Centers for Disease Control and Prevention recommends physician referral only when hemoglobin is less than 9.0 g/dL or hematocrit is less than 27.0%. 2 This patient's hemoglobin is above this threshold and she is not acutely symptomatic.
Transfusion carries risks of infection, alloimmunization, and transfusion reactions that are not justified for mild anemia. 4
Why IV Iron is Not First-Line
Intravenous iron should be reserved for specific indications that are not present in this case. The American College of Obstetricians and Gynecologists recommends IV iron for severe anemia, intolerance to oral iron, or lack of response to oral iron after 4 weeks despite compliance. 1
This patient should first receive a trial of oral iron. Only if she fails to respond after 4 weeks (defined as less than 1 g/dL increase in hemoglobin) or cannot tolerate oral therapy should IV iron be considered. 2, 1
Specific Treatment Protocol
Dosing Regimen
Prescribe ferrous sulfate 325 mg (65 mg elemental iron) once or twice daily to achieve 60-120 mg elemental iron per day. 2, 1, 3
Recent evidence suggests alternate-day dosing may be as effective as daily dosing with fewer side effects, though daily dosing remains standard. 4, 5
Dietary Counseling
- Provide counseling on iron-rich foods and factors that enhance iron absorption. 2, 1 Recommend taking iron with vitamin C to improve absorption and avoiding concurrent intake with antacids or calcium supplements. 3
Monitoring Response
Reassess hemoglobin after 4 weeks of treatment. 2, 1 The expected response is an increase of ≥1 g/dL in hemoglobin or ≥3% in hematocrit. 2, 1
If no response after 4 weeks despite compliance and absence of acute illness, perform additional testing including mean corpuscular volume, red cell distribution width, and serum ferritin. 2, 1 Consider alternative diagnoses such as thalassemia minor or other causes of anemia.
Dose Adjustment After Response
- Once hemoglobin normalizes for gestational age, reduce the dose to 30 mg elemental iron daily for maintenance throughout pregnancy. 2, 1
Common Pitfalls to Avoid
Do not assume this requires IV iron or transfusion based solely on the hemoglobin value. Mild anemia (Hb 9.0-10.9 g/dL) responds well to oral therapy in most cases. 1, 4
Warn the patient about gastrointestinal side effects (nausea, constipation, dark stools) which are common but generally self-limited. 3, 4 These side effects often lead to non-adherence, so counseling is critical.
Do not take iron within 2 hours of tetracycline antibiotics as iron interferes with tetracycline absorption. 3