What is the next step in managing iron deficiency anemia in a 30-week pregnant woman with Hb 110 g/L, Hct 0.33, RBC 3.61 x 10^12/L, and ferritin 47 ng/mL?

From the Guidelines

The next step in managing this pregnant woman is to start oral iron supplementation with ferrous sulfate 325 mg once or twice daily (providing 65-130 mg of elemental iron). Despite her ferritin level being within normal range for pregnancy (>30 ng/mL), her hemoglobin of 110 g/L indicates mild anemia by pregnancy standards, where the lower limit is typically 110-115 g/L in the third trimester 1. Iron supplementation is warranted because pregnancy increases iron demands significantly, with requirements rising from 1-2 mg/day in early pregnancy to 6-8 mg/day in the third trimester to support fetal development, placental growth, and maternal blood volume expansion.

Key Considerations

• The supplement should be taken between meals with vitamin C (such as orange juice) to enhance absorption, and separated from calcium-containing foods, tea, coffee, and antacids which can reduce absorption.
• Side effects may include constipation, nausea, and black stools; starting with once-daily dosing and gradually increasing can improve tolerance.
• A follow-up hemoglobin check should be performed in 2-4 weeks to assess response, with an expected increase of approximately 1 g/L per day or 20 g/L over 3-4 weeks if the anemia is truly due to iron deficiency.

Rationale

The decision to start oral iron supplementation is based on the patient's mild anemia and the increased iron demands during pregnancy, as recommended by the U.S. Preventive Services Task Force 1. The goal of treatment is to improve maternal hematologic indexes and reduce the risk of adverse maternal and infant health outcomes.

Monitoring and Follow-up

Regular monitoring of the patient's hemoglobin levels and iron stores is essential to assess the response to treatment and adjust the supplementation regimen as needed. Additionally, the patient should be educated on the importance of adhering to the supplementation regimen and reporting any side effects or concerns to her healthcare provider.

From the Research

Patient's Current Status

• Hemoglobin (Hb) level: 110 g/L
• Hematocrit (Hct) level: 0.33
• Red Blood Cell (RBC) count: 3.61 x 10^12/L
• Ferritin level: 47 ng/mL
• Gestational age: 30 weeks

Diagnosis and Treatment of Iron Deficiency Anemia

• According to 2, iron deficiency and/or iron deficiency anemia (IDA) complicate nearly 50% of pregnancies globally, and iron deficiency can cause a range of symptoms.
• The American College of Obstetricians and Gynecologists recommends screening for anemia with a complete blood count in the first trimester and again at 24 0/7 to 28 6/7 weeks of gestation, as stated in 3.
• For patients with iron deficiency anemia who cannot tolerate, cannot absorb, or do not respond to oral iron, intravenous iron is preferred, as mentioned in 3 and 4.

Next Recommended Step

• Since the patient's Hb level is 110 g/L, which is above the threshold for anemia in pregnancy, and her ferritin level is 47 ng/mL, indicating some iron stores, the next step would be to continue monitoring her Hb and ferritin levels.
• As suggested by 5, oral iron remains an option for treatment, and absorption is improved with every other day dosing.
• However, given the patient's gestational age and the fact that she is already showing some improvement in her Hb level, it may be beneficial to consider intravenous iron supplementation if her iron levels do not continue to improve, as recommended by 2 and 5.

Key Considerations

• The patient's iron deficiency anemia should be managed to prevent adverse maternal and fetal outcomes, as highlighted in 2 and 3.
• The choice of treatment, whether oral or intravenous iron, should be based on the patient's individual needs and response to treatment, as discussed in 3 and 4.
• Regular monitoring of the patient's Hb and ferritin levels is crucial to assess the effectiveness of treatment and make any necessary adjustments, as emphasized in 5.