You have donated for years, you are proud of it, and your periods have become heavier. Donation services check your haemoglobin before every session — but haemoglobin is not the first thing to fall when iron runs low, so it is entirely possible to keep passing the screen while your stores empty. This is a small, specific problem with a straightforward fix.
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 medical advice. We are not telling anyone to stop donating. Donation matters and this is about doing it sustainably.
Why this happens
Two things collide in perimenopause.
Periods often get heavier and less predictable before they stop, and heavy menstrual loss is the commonest cause of iron deficiency in women of this age — see heavy periods in perimenopause.
Each donation removes a meaningful amount of iron. That is fine when losses and intake balance. It stops being fine when monthly loss has quietly doubled.
The result is a slow drawdown that nothing in the process is designed to catch.
The screening gap, stated plainly
Donation services check haemoglobin before you give. That is a safety check for the donation itself, and it works for that.
But ferritin — iron stores — falls first. Haemoglobin only drops once stores are substantially depleted. So there is a window, sometimes a long one, in which you are iron-deficient, symptomatic, and still passing the screen every time.
Some services now measure ferritin in some donors, and practice differs by country and is changing. Most do not do it routinely. Ask yours what it checks rather than assuming a pass means your iron is fine.
The symptoms of that window are the ones you are probably attributing to the transition: exhaustion, brain fog, hair shedding, breathlessness on stairs, palpitations, restless legs, feeling cold, cravings for ice. See low ferritin in perimenopause and symptoms most often misread as menopause.
What to do
Ask for a ferritin test, separately from donation, especially if your periods have become heavier or you are tired in a way sleep does not fix. It is a standard test and it belongs in the same set as thyroid, B12, HbA1c and vitamin D — see which tests to ask for and our free printable blood test sheet.
Tell the donation service about your periods. Heavy menstrual bleeding is relevant information and they would rather know. Ask what they check and what interval they would suggest for you.
Space donations further apart if you are donating at the minimum interval and your periods have changed. Intervals are minimums, not targets, and several countries already set different minimums for women partly for this reason.
Treat the bleeding rather than the deficiency alone. Iron replacement while losing the same amount each month refills nothing. Heavy bleeding is treatable — see comparing the treatment options.
Do not start iron speculatively. Take it for a confirmed deficiency, because iron overload is harmful — this is one of the few places where guessing does damage rather than nothing. If you are taking it, take it properly: vitamin C alongside, away from tea, coffee and calcium, and alternate-day dosing is often better absorbed and better tolerated — see how to actually take iron.
If iron is low and your periods do not explain it, that needs investigating rather than supplementing — particularly after menopause, when periods are no longer an explanation. See when iron is not the answer.
Whether to keep donating
Most people can, with adjustments. The realistic options, in the order worth trying:
- Get ferritin checked and find out where you actually are
- Lengthen the interval rather than stopping
- Treat the heavy bleeding, which fixes the underlying arithmetic
- Pause while you correct a deficiency, then return
Stopping permanently is rarely the necessary answer, and framing it as all-or-nothing is what leads people to either quit or push on while depleted.
If you have been deferred for low haemoglobin, that is not a minor administrative event. It means you were anaemic. Treat it as a finding worth investigating rather than a reason to eat more spinach and try again in three months.
A note if you are on hormone therapy
Being on hormone therapy does not itself prevent donation in most places, but rules differ. Check with your service. And if a hormonal IUD has stopped your periods, your iron picture may have improved considerably — worth knowing, because it changes the calculation in the other direction. See when does my coil come out.
What to say
"I've donated regularly for years and my periods have got much heavier over the last two years. My haemoglobin has always passed, but I understand ferritin falls first — could I have it checked? And I'd like to talk about the bleeding itself."
That names the gap, asks for the right test, and puts the cause on the table rather than only the consequence.
Our free 30-day symptom tracker records the bleeding that usually explains it, the free printable visit prep sheet turns it into one page, and the free 2-minute Menova self-check organizes your wider symptom picture — no account, not a diagnosis, and your answers never leave your device.
This article is general education, not medical advice or a diagnosis, and not advice to stop donating blood. Donation eligibility rules, screening practice and intervals differ by country and change over time — confirm with your own donation service. Do not supplement iron without a confirmed deficiency.
Sources: NHLBI — Iron-Deficiency Anemia, NIH Office of Dietary Supplements — Iron, NICE NG88 — Heavy Menstrual Bleeding, and NHS — Iron Deficiency Anaemia.