Iron in Pregnancy: Why Your Needs Rise, the Signs Women Miss, and How to Support Healthy Levels

Here’s the plain answer to the question most women are really asking: iron requirements rise significantly in pregnancy — from 18 mg a day to 27 mg (NHMRC, 2006) — because your body is building extra blood volume and supporting your baby’s growth. Whether you need a supplement, though, comes down to your own results, not a guess. Let me walk you through how I think about it.

Why your iron needs climb in pregnancy

Pregnancy is a quietly enormous physiological event. Over nine months your blood volume expands by close to half, which means a great many new red blood cells to build — and iron sits at the centre of that work. At the same time, your baby is drawing on your stores to grow, and laying down a reserve to carry them through their first months of life, when milk is naturally low in iron.

That’s why recommended intake climbs to 27 mg a day in pregnancy, up from 18 mg for non-pregnant women (NHMRC, 2006), with demand highest through the second and third trimesters as growth accelerates. It’s a genuine ask of the body — and the reason iron comes up in almost every pregnancy consult I have.

The signs that get written off as “just pregnancy”

Here’s the tricky part: when iron stores run low, the lived experience of it overlaps almost perfectly with an ordinary pregnancy. Women describe things like:

• tiredness that rest doesn’t seem to touch

• feeling breathless on stairs they used to take without thinking

• looking paler than usual, or feeling the cold more

• noticeable hair shedding

• a flat, running-on-empty feeling

Each of these can be part of a perfectly normal pregnancy, which is exactly why low iron in pregnancy is so easy to wave away. I’m not asking you to scrutinise every symptom — only to know that these experiences are worth raising with your GP or midwife rather than quietly pushing through.

Test, don’t guess — and know that “normal” isn’t always “ample”

If you take one thing from this article, make it this: iron is individual, and the only way to know where you stand is to test. When you have bloods done, ask whether ferritin is included, not just haemoglobin. Ferritin reflects your iron stores — the reserve in the tank — and it can fall well before a standard count shifts.

It’s also worth understanding that a result sitting inside the “normal” range isn’t the same as one that’s comfortably ample, particularly when your demand is climbing week by week. That gap is exactly what caught out the woman I opened with: in range, but hugging the floor of it. So if your ferritin comes back low-but-normal and you feel wrung out, that’s a conversation to have with your practitioner, not a box to tick and move past. I usually suggest checking early in pregnancy and again later on, since the demand curve keeps shifting.

Food first: getting the most from the iron on your plate

Before any supplement conversation, I start with the plate — because food does a great deal of the work, and the habits are worth keeping for life. Dietary iron comes in two forms, and the difference matters. Haem iron, from animal foods, is the more readily absorbed:

• red meat (the richest source)

• chicken and other poultry

• fish and seafood

Non-haem iron, from plants and eggs, is absorbed less efficiently — but there’s plenty you can do to help it along:

• legumes and lentils

• tofu and tempeh

• dark leafy greens like spinach and silverbeet

• wholegrains and iron-fortified cereals

• eggs

Two small habits change how much of that iron you actually take up. The first is to pair non-haem iron with vitamin C — a squeeze of lemon over lentils, tomato through a bean dish, or a piece of citrus or kiwifruit with breakfast — which shifts the iron into a form your gut absorbs more easily. The second is to mind your timing: the tannins in tea and coffee, and calcium-rich foods or supplements, both compete with iron, so keep your cuppa for between meals rather than alongside your iron-rich plate. None of this calls for a special diet — mostly pairing and timing, the kind of small adjustments that quietly add up.

When food isn’t enough: form, timing, and a gentler approach

When testing shows iron is worth supplementing, two details make a real difference to how you feel taking it. The first is form. Traditional iron salts such as ferrous sulfate are effective but famously hard on the stomach — nausea and constipation are common, which is the last thing you want when pregnancy may already be serving up plenty of both. A chelated form such as iron bisglycinate is generally better tolerated, and tolerance is what keeps you consistent.

The second is timing, and it surprises most people. Research suggests that for some, taking iron every second day rather than daily can actually improve how much is absorbed from each dose — a large daily hit nudges up a hormone called hepcidin that temporarily dampens absorption (Stoffel et al., 2017). Less can genuinely be more, and it’s often easier on the gut too. It’s a worthwhile thing to raise with your GP, midwife or naturopath rather than self-prescribing a schedule.

This thinking is exactly why our range is built the way it is. Our prenatal, EverNatal, is iron-free by design — not because iron doesn’t matter, but because it matters enough to dose to the individual, alongside testing, rather than baking a one-size-fits-all amount into every prenatal. And for women who do need to top up, IronBiotic provides iron as iron bisglycinate (Ferrochel®), a gentle, well-tolerated form, paired with a probiotic. Iron contributes to normal energy production and to carrying oxygen around the body — the quiet, everyday biochemistry behind feeling like yourself. The decision of whether you need it, though, belongs with you and your practitioner, guided by your ferritin number.

Iron in pregnancy: your questions, answered

How much iron do I need in pregnancy?

The recommended intake rises to 27 mg a day in pregnancy, up from 18 mg for non-pregnant women (NHMRC, 2006), reflecting your expanding blood volume and your baby’s growth. Whether you meet that through food alone or need extra depends on your individual iron stores — which is why testing matters.

What are the signs of low iron in pregnancy?

Common experiences include persistent tiredness, breathlessness with everyday activity, looking pale, feeling the cold, and increased hair shedding. Because these overlap with ordinary pregnancy, the only reliable way to know is a blood test — ask your GP or midwife to check your ferritin, not just your haemoglobin.

Can I get enough iron from food alone in pregnancy?

Many women can, especially with a mix of haem sources (red meat, poultry, fish) and non-haem sources (legumes, leafy greens, wholegrains) paired with vitamin C to aid absorption. Others — particularly those starting with low stores — may need extra, a decision best made with your practitioner based on your results.

So: take your own energy seriously. Start with food, ask for your ferritin number so you’re working from fact rather than a hunch, and if iron is indicated, choose a form you tolerate so you can stay the course. Growing a baby is reason enough to look after yourself properly.