How should I manage a 43-year-old woman with three days of generalized weakness, anemia (hemoglobin 8.4 g/dL, normocytic) and a recent four‑day history of heavy menstrual bleeding?

Management Approach

This is iron deficiency anemia (IDA) secondary to heavy menstrual bleeding in a premenopausal woman—initiate oral iron supplementation immediately (ferrous sulfate 325mg daily on an empty stomach or with meals if not tolerated) and refer to gynecology for menstrual bleeding management. 1

Diagnostic Confirmation

Your patient has:

• Normocytic anemia (Hb 8.4 g/dL, MCV 87.2 fL—technically normocytic but likely early iron deficiency)
• Hypochromic features (MCH 24.5, MCHC 28.1—both low, indicating iron deficiency)
• Clear bleeding source (4-day heavy menstrual bleeding)

The low MCH and MCHC are the key findings here—these indicate iron deficiency despite the normal MCV. Early IDA often presents with normocytic indices before progressing to microcytosis. The recent heavy menstrual bleeding provides the obvious source.

Check a ferritin level to confirm iron deficiency (threshold <45 mg/dL in the setting of anemia per AGA guidelines). 1 However, given the clear clinical picture of menstrual blood loss with hypochromic indices, you can start iron replacement empirically while awaiting results.

Immediate Management Algorithm

Step 1: Iron Replacement

• Start ferrous sulfate 325mg once daily (or ferrous fumarate/ferrous gluconate—all equally effective) 1
• Take on empty stomach for best absorption, but if not tolerated due to nausea/constipation/abdominal pain, take with meals 1
• Add vitamin C 500mg with the iron dose to enhance absorption 1
• Avoid taking with calcium or high-fiber foods if possible

Common pitfall: Many providers underdose or patients stop due to side effects (constipation 12%, diarrhea 8%, nausea 11%). 1 Counsel the patient upfront about these effects and that taking with food is acceptable if needed.

Step 2: Address the Bleeding Source

• Urgent gynecology referral for heavy menstrual bleeding management
• This is the root cause—iron replacement alone will fail if bleeding continues uncontrolled
• Gynecology options may include hormonal therapy, tranexamic acid, or procedural interventions

Step 3: Rule Out Additional Causes

While menstrual bleeding is the obvious culprit in a premenopausal woman, do not assume this is the only cause without basic screening: 2

• Celiac serology (tissue transglutaminase IgA with total IgA)—coeliac disease is a common cause of IDA in the UK and often coexists 2
• Dietary history: Vegetarian/vegan diet, poor iron intake
• Medication review: NSAIDs, aspirin, anticoagulants
• H. pylori testing if upper GI symptoms present 1

You do NOT need GI endoscopy in this premenopausal woman with clear menstrual blood loss unless: 2

• She fails to respond to iron replacement after 3 months
• She has GI symptoms (dyspepsia, change in bowel habits, weight loss)
• Celiac serology is positive
• She becomes postmenopausal

Step 4: Consider IV Iron If:

• Severe symptoms (she has significant weakness with Hb 8.4)
• Intolerance to oral iron develops
• Ongoing heavy bleeding that cannot be immediately controlled
• Failure to respond to oral iron after 4-6 weeks

IV iron formulations allow faster repletion and bypass GI side effects, though oral iron should be tried first in most cases. 1

Follow-Up Plan

• Recheck CBC in 4 weeks: Expect Hb rise of 1-2 g/dL if compliant and bleeding controlled
• Continue iron for 3-6 months after Hb normalizes to replete stores
• Recheck ferritin once Hb normalized to confirm adequate repletion (target >50 mg/dL)

Key Pitfalls to Avoid

1. Don't stop iron when Hb normalizes—stores need months to replete 1
2. Don't ignore the bleeding source—iron alone is futile if hemorrhage continues
3. Don't assume menstruation is the only cause—screen for celiac disease 2
4. Don't delay gynecology referral—this patient needs definitive bleeding control

The weakness will improve within 2-4 weeks of starting iron as the anemia corrects, but full symptom resolution requires both iron repletion and bleeding control.