Iron deficiency is the usual cause of anaemia in perimenopause, and it is not the only one. When iron treatment does not work — or when the blood count improves and you still feel terrible — the next step is not more iron.
Where we stand: Menova is an independent publication. We sell no supplements or tests, we are not your doctor, and this is general education, not a diagnosis. Do not take iron without a confirmed deficiency.
Start with the numbers you were given
"Your bloods were fine" is not enough information. Ask for:
- Haemoglobin, and whether it is below your lab's range
- MCV — the average red cell size. This single number splits the causes
- Ferritin — iron stores, which fall before haemoglobin does
- B12 and folate
See reading your own blood test results.
What MCV tells you
Small cells (low MCV) — most often iron deficiency. Also thalassaemia trait, which is inherited, lifelong, and frequently mistaken for iron deficiency; women in this position are sometimes given iron for years without benefit. A ferritin that is normal alongside small cells is the clue.
Large cells (high MCV) — B12 or folate deficiency, alcohol, thyroid disease, some medications, and rarely a bone marrow problem — see B12 deficiency in midlife.
Normal-sized cells — anaemia of chronic disease, kidney disease, thyroid disease, or an early mixed picture.
A mixed deficiency — iron plus B12 — can produce a normal MCV while both are low, which is one reason to ask for the individual values rather than accepting a summary.
If iron treatment has not worked
Work through these in order rather than increasing the dose.
Are you taking it in a way that absorbs? Coffee and tea an hour either side, calcium separated, vitamin C alongside, and alternate-day dosing which is often better absorbed and better tolerated — see how to actually take iron.
Is the loss ongoing? Supplementing while losing the same amount monthly does not refill anything. Heavy perimenopausal bleeding is treatable, and treating it is the actual fix — see heavy periods in perimenopause and comparing the treatment options.
Is there malabsorption?
- Coeliac disease, a classic and frequently missed cause. Get tested before cutting gluten out — see coeliac disease and menopause
- Long-term acid-reducing medication, which reduces iron and B12 absorption
- Previous gastric or bariatric surgery
- Inflammatory bowel disease
Is there bleeding somewhere else? This is the one that matters most. Iron deficiency without an obvious cause — and particularly after menopause, when periods are no longer an explanation — needs investigating. Gastrointestinal blood loss is the concern, and bowel screening commonly begins at 45 — see haemorrhoids and bowel changes and health screening in your 50s.
Is it actually iron deficiency? See the MCV section above.
When iron infusion is appropriate
Under-offered, and worth asking about if:
- Oral iron is not tolerated in any form
- Deficiency is severe
- Absorption is impaired
- You have been struggling for months without your ferritin moving
It corrects stores quickly. Ask whether it is available to you.
Anaemia of chronic disease
Where inflammation from an ongoing condition — autoimmune disease, chronic infection, kidney disease, some cancers — interferes with how the body uses iron.
The confusing part: ferritin rises with inflammation, so it can look normal or high while the body is still functionally short of usable iron. Iron supplements do not help, and treating the underlying condition does.
If you have an inflammatory condition and persistent anaemia, this is worth raising — see autoimmune conditions and menopause.
Kidney and thyroid
Kidney disease reduces production of the hormone that stimulates red cell production, and is easy to check with a blood test.
Thyroid disease causes anaemia in either direction, and it also causes every other symptom you are attributing to the transition — see perimenopause versus thyroid.
The symptoms, and why they get missed
Every one of these is attributed to menopause:
- Exhaustion that sleep does not fix
- Breathlessness on stairs
- Palpitations — see heart palpitations in perimenopause
- Brain fog and poor concentration
- Feeling cold — see cold flashes and chills
- Restless legs — a strong and frequently missed association; see restless legs in menopause
- Hair shedding
- Headaches, brittle nails, mouth ulcers
- Dizziness on standing — see dizzy when you stand up
- Cravings for ice, which is specific and worth mentioning
Get urgent care for
- Chest pain or severe breathlessness
- Fainting
- Black or tarry stools, or vomiting blood
- Very heavy bleeding you cannot control
What to ask
"My haemoglobin and ferritin were low and I've been on iron for four months without feeling better. Could I have the actual numbers, including MCV? And could we look at why I'm losing iron — coeliac screening, and whether my periods need treating — rather than just continuing the supplement?"
That asks for the numbers, names the two commonest missed causes, and shifts the question from the supplement to the cause.
Our free 30-day symptom tracker records the bleeding that usually explains it, and the free printable visit prep sheet turns it into one page.
The free 2-minute Menova self-check organizes your wider symptom picture — no account, not a diagnosis, and your answers never leave your device.
The rule
Iron deficiency is a finding, not a diagnosis. The question is always why — and after menopause, or when treatment is not working, that question needs answering rather than another prescription.
Our fuller guide is low ferritin in perimenopause.
This article is general education, not medical advice or a diagnosis. Do not supplement iron without a confirmed deficiency — iron overload is harmful. Unexplained anaemia requires investigation by a licensed clinician.
Sources: NHLBI — Anemia, NIH Office of Dietary Supplements — Iron, NIDDK — Celiac Disease, and NHS — Iron Deficiency Anaemia.