The Journal · After Birth
Iron after birth: why you feel like this
Everyone tells you it’s the sleep. Sometimes it is. But a flattened, breathless, cold-handed kind of tired has another common cause, and it is straightforward to check.
Six weeks in, someone will ask how you are and you will say tired, and they will say of course you are, and the conversation will move on. Which is fair enough — you are tired, and the baby is up twice a night.
But there is a particular kind of postnatal tired that sleep does not explain and does not fix. It is heavier. You get out of breath putting the pram in the car. Your hands are cold in a warm room. You feel your heart when you stand up. There is a headache behind the eyes most afternoons, and hair in the plughole. If that is nearer your experience than ordinary exhaustion, iron is worth ruling in or out.
Where the iron went
Iron is used to make haemoglobin, the part of your red blood cells that carries oxygen around the body. Three things in the last year will have drawn on it: pregnancy itself, which expands your blood volume considerably and builds the baby's own stores; blood loss at birth, which is normal and can still be substantial; and then the weeks of recovery afterwards.1
None of that is a warning sign. It is the ordinary arithmetic of having had a baby. It simply means the tank starts lower than it did, and the symptoms of low iron look almost exactly like the symptoms of new parenthood — which is precisely why it gets missed for months.
Iron deficiency after birth is common, easy to test for, and treatable. The reason it goes unaddressed is rarely that it's hard to fix. It's that everybody, including you, has a very good alternative explanation for feeling terrible.
Get it checked
This is the one thing in this article to actually do. Ask your GP for a full blood count and ferritin — ferritin is the measure of stored iron, and it can be low while a standard blood count still looks acceptable. Mention the specific symptoms rather than just “I'm exhausted”, because the specific ones are what prompt the test.2
If it comes back low, you'll likely be offered a supplement. Take it, and take it for as long as you're told to, which is usually longer than you feel you need — stores take months to refill after the symptoms have gone. Food cannot do this job alone at the pace you'd want.
What food does well
Food's job is topping up and holding steady, and it does that job properly. UK adult women aged 19–49 need around 14.8mg of iron a day.1
The two kinds of iron
Iron in meat, fish and eggs (haem iron) is absorbed readily. Iron in beans, lentils, tofu, nuts, seeds, dried fruit and fortified cereals (non-haem iron) is absorbed less readily — but there is a lot of it about, and you can improve the absorption considerably.
The absorption levers
- Add vitamin C. Something acidic and fresh alongside plant iron makes a real difference: lemon squeezed over lentils, tomatoes in the chilli, a satsuma after breakfast, peppers in the stir-fry.
- Move the tea. Tannins in tea and coffee bind iron and reduce how much you absorb. You do not have to give up tea — just try to leave an hour either side of the meals that are doing the iron work. In practice this usually means tea between meals rather than with them.
- Eat it together. A small amount of meat or fish in the same meal also improves absorption of the plant iron on the plate, which is a good argument for the sort of cooking where a little meat stretches through a lot of vegetables.
Five things that require almost nothing of you
- Fortified cereal with a satsuma. Check the box: many are fortified with iron, and the vitamin C alongside is doing real work.
- A pouch of ready-cooked lentils tipped into anything, with lemon over it.
- Eggs. Two eggs, one pan, four minutes, one hand.
- Tinned sardines on toast. Iron, omega-3 and calcium in something that needs a fork and a tin opener.
- Dried apricots and a handful of pumpkin seeds in the place you sit to feed. This is the one that actually happens.
If you are breastfeeding
Your own iron level has very little effect on the iron in your milk — the body protects milk composition remarkably well. So topping up iron is about you, not about the feeding. That matters, because it removes the guilt angle: you are not doing this for the baby's sake, you are doing it because you deserve to not feel like this.
Keep taking 10 micrograms of vitamin D a day. Breastfed babies are also advised to have a daily vitamin D supplement of 8.5 to 10 micrograms from birth, unless they are having more than 500ml of formula a day, which is already fortified.3
The part we most want you to hear
Feeling this flat is not the price of having a baby, and it is not something you have to be gracious about for another six months. It is a symptom, it has causes, and at least one of the common causes takes one blood test and a bottle of tablets to address.
Ask. Then eat the apricots while you wait for the appointment.
Sources & further reading
A note on what this is. This article is general information, written by registered nutritional therapists and referenced above. It is not a diagnosis and it is not a substitute for advice about you. If you are pregnant, breastfeeding, taking medication, or managing a health condition, please talk to your GP, midwife, health visitor or a registered practitioner before making changes — and always speak to them first if something is worrying you.