A 32-year-old multigravida (G3P2) at 24 weeks of gestation presents for routine antenatal check-up. Her vital signs are stable (BP 120/78 mmHg), weight gain is appropriate, and urine dipstick is normal. Her hemoglobin is 10.2 g/dL (baseline at 12 weeks was 11.8 g/dL). She denies any symptoms. What is the most appropriate next step in management?