A 26-year-old woman at 28 weeks gestation presents with pallor. Hemoglobin is 7.8 g/dL, MCV 112 fL, MCH 36 pg, and peripheral smear shows hypersegmented neutrophils. Serum vitamin B12 is 80 pg/mL (normal 200-900). Serum folate is normal. Which statement about her management is correct?

• A Oral folic acid 5 mg daily is the treatment of choice since folate deficiency is most common in pregnancy
• B The infant will require lifelong vitamin B12 supplementation regardless of feeding method because maternal stores are depleted
• C Packed red cell transfusion is mandatory before 32 weeks regardless of symptoms because hemoglobin is below 8 g/dL
• D Intramuscular vitamin B12 1000 mcg weekly until delivery is indicated, and the fetus is at no increased risk for neural tube defects ✓

Explanation

Macrocytic anemia with hypersegmented neutrophils and low D12 confirms vitamin D12 deficiency. In pregnancy, oral D12 absorption is unreliable, so parenteral D12 (1000 mcg IM weekly) is standard. Distractor A is wrong because folate is normal and folic acid does not correct D12 deficiency neurological damage. Distractor C overstates the threshold for transfusion; transfusion is guided by symptoms and hemodynamic status, not an absolute cutoff. Distractor B is incorrect because infant D12 status depends on maternal stores and infant diet, not automatically lifelong supplementation.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.