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Managing Iron Deficiency in Pregnancy (including Anaemia)

One of the most common complaints in pregnancy, particularly the 2nd and 3rd trimesters of pregnancy is iron deficiency and in severe cases iron deficiency anaemia. In fact, a huge 12% of Australian women are diagnosed with iron deficiency anaemia in pregnancy, that is more than 1 in 10 women walking around feeling exhausted, out of breath and at risk of fetal growth restriction and preterm birth!
It is important that a woman’s health care team manage her iron levels from preconception through to post-birth, (highlighting the importance of preconception care). Whilst it is a uniquely challenging task to maintain adequate iron stores during pregnancy with proper management and adequate testing a woman may not need to consider IV iron and can continue her pregnancy without feeling flat-on-the-ground exhausted.

What is the difference between iron deficiency and iron-deficiency aneamia

Haemoglobin is a protein found in our red blood cells. The body uses iron to make haemoglobin, so if there is a low supply of iron for an extended period of time it can lead to anaemia.

Low iron long term –> low haemoglobin –> iron deficiency aneamia

Anaemia may be caused by other factors outside of iron deficiency however for simplicities sake we will only discuss iron-deficiency anaemia.
– Iron deficiency is defined as low iron (ferritin) stores in the body, in Australia that is a ferritin of <30u/L. – Iron deficiency anaemia on the other hand is characterised by both low ferritin <30ug/L and low haemoglobin.

Why is iron deficiency/or Anaemia so common in pregnancy?


A dramatic drop in ferritin levels and haemoglobin is seen in pregnancy, predominantly in the second and third trimesters due to haemodilution. Haemodilution is the increase in plasma volume and to a lesser extend red cell mass caused in pregnancy to facilitate increased blood and nutrient flow to the growing baby. This effect is so pronounced that in Australia we have changed our guidelines to account for the dilution.

A woman’s blood volume increases by 50% by the end of pregnancy.

Compromised gastrointestinal function

Iron absorption is significantly enhanced by gastric acid. Reduced gastric acidity impairs the conversion of dietary ferric iron to the more absorbable ferrous form. Often gastrointestinal issues such as pregnancy reflux are treated with proton pump inhibitors (PPI’S) which suppress acid production, this can affect the uptake of iron.

Optimal levels during preconception and pregnancy

Testing for deficiency

Conventionally a woman has her iron and haemoglobin tested upon finding out she is pregnant, alongside HCG, then again at 28 weeks when often only haemoglobin is tested and not iron studies.
Naturopathically we recommend testing 3 months prior to trying to conceive, then a check up once you are pregnant. If a deficiency exists then we recommend a test at 12 weeks then every 8 weeks until the deficiency is corrected (w20/28/36).
The tests to request are FBC and iron studies.

Supplementing to improve iron stores

Whilst it makes logical sense to supplement with higher doses of iron when a deficiency exists studies are showing us that this may not actually be true and considering the high rate of constipation in those women on high dose iron this message comes with a sigh of relief.
In a 2009 study it was shown that low-dose iron supplements may be effective at treating anaemia in pregnancy with less gastrointestinal side effects compared with high-dose supplements.
The study showed only an 8g/l difference in haemoglobin scores between those women supplementing with 20mg as with those supplementing with 80mg/day. So we can see that double the dose doesn’t lead to double the effect.
In Australia, doses of up to 100mg/day of iron are not uncommon.
Clinically, we find the best results when we focus on the combination of
Dietary iron every other day + 24-48mg/day supplemental iron + co-factors

Iron absorption: Looking at co-factors

A 2015 study was conducted to evaluate the efficacy and safety of lactoferrin in comparison to ferrous sulphate (iron) for the treatment of iron deficiency anemia during pregnancy and found lactoferrin was more effective than ferrous sulfate over a two-month period in pregnant women with anaemia, with fewer gastrointestinal adverse events and better treatment acceptability.
We recommend 100-1000mg of lactorrin in conjunction with iron supplementation.


Lactobaccilus plantarum 299V (LP229V)

Intake of Lp299v with iron for four weeks increased ferritin and haemoglobin levels more than iron alone. Another study in a pregnant population showed similar results a lower rate of both iron deficiency (59% vs 78% ) and iron deficiency anemia (7.4% vs 21%,) at week 35.

Iron inhibitors

– Decrease your concurrent intake of iron inhibitors such as tea, coffee, red wine, dairy and calcium supplementation and PPI’s by 1-2 hours.

Dietary sourcse of iron

Dietary iron comprises haem (animal sources) and non-haem iron (cereal and vegetable sources). Haem iron (bound to Hb and myoglobin) is better absorbed than non-haem iron and includes.

Best iron source

– Slow-cooked beef or pork:
We recommend red meat 2-7 days a week depending on your ferritin and haemoglobin levels. Often in trimester 1 women are adverse to eating meat so this recommendation is better indicated for women in their 2nd and 3rd trimesters of pregnancy.

Other iron sources

– Mussels

– Oats

– Chanterelle mushrooms

– Spinach

– Pistachios

– Cashews

– Millet
Learn more about food sources of iron here.

If you have been diagnosed with an iron deficiency or iron deficiency anaemia and would like help managing your levels book in for a FREE base chat with one of our qualified practitioners here.
To learn more about the importance of iron in preconception care read our blog here.
Jennifer Ward, Adv dip Nat, BCom Econ, competing Masters Repro MedJennifer is a qualified naturopath with a focus on preconception, pregnancy, postpartum

Learn more about Jennifer here Book a session with Jennifer hereFor speaking enquiries on this topic get in touch at