Iron Deficiency Without Anemia: Why Pregnant Women Should Get Screenings For Iron Deficiency

Iron deficiency is the most common nutrient deficiency globally and is especially common in pregnant women when iron needs are highest. Iron deficiency is easy to screen for, yet you might be surprised to learn that many women aren’t getting proper testing. When left untreated, iron deficiency poses health risks to mothers and their babies. 

Since treatment is quite simple, typically only requiring an increase in iron-rich foods and iron supplementation, it is important to be educated about iron during pregnancy and advocate for proper testing in the health care system. This article will provide the information required to do just that. 

Keep reading to learn more about: 

• What iron deficiency is and how it differs from iron deficiency anemia
• Symptoms of iron deficiency to be aware of
• Risk factors for iron deficiency 
• Testing and prevalence of iron deficiency in pregnancy
• Ways to reverse iron deficiency 
• What to be aware of with iron supplements and why liposomal iron is superior

Let’s dive into this important topic! 

What Is Iron Deficiency Without Anemia?

Anemia is a condition where you don’t have enough healthy blood cells to transport the amount of oxygen required by cells and tissues throughout the body. You may be familiar with iron deficiency anemia, the most common form of anemia that is due to low iron status. (Source 1)

Of note, anemia may also be caused by low folate (also known as vitamin B9 or folic acid) or low vitamin B12 status as these nutrients are required for the methylation cycle that builds blood cells. Autoimmunity is another cause of anemia. 

Iron deficiency anemia is diagnosed with a blood test for hemoglobin (also spelled haemoglobin). Hemoglobin is the iron-containing protein structure in red blood cells that carries oxygen. Iron deficiency anemia is diagnosed when hemoglobin is at or below 13 g/dL (130 g/L) for men and 12 g/dL (120 g/L) for women. (Source 2)

However, it’s possible to have iron deficiency without anemia. This means that iron levels and iron stores are low, but the hemoglobin level remains within the normal range.  

Serum ferritin is the most sensitive blood test for iron deficiency and represents iron in its storage form. Where hemoglobin may be the last place for iron to deplete, ferritin will be the first. Ferritin levels below 30 μg/L suggest iron deficiency independent of other iron labs, especially when iron deficiency symptoms are present. (Source 2) Some research suggests that levels above 45 μg/L is a more optimal range. (Source 3)

To see a full list of iron labs, such as hematocrit, along with functional (optimal) ranges, see my article, Iron Supplements – Pregnancy, Postpartum and Menorrhagia. 

Symptoms Of Iron Deficiency

Iron deficiency symptoms may be the same as symptoms of anemia. It’s possible to have prolonged, severe and even debilitating symptoms related to iron deficiency, without meeting the diagnostic criteria for anemia. 

Possible symptoms of low ferritin concentrations include: 

• Fatigue 
• Weakness
• Chest pain
• Shortness of breath
• Hair loss
• Poor appetite
• Brain fog
• Muscle and joint pain
• Weight gain
• Headache
• Heart palpitations or arrhythmia
• Sleep disturbances
• Difficulty swallowing
• Restless legs (Source 2)

In some cases iron deficiency is misdiagnosed or mistaken for other conditions including subclinical hypothyroidism, chronic fatigue, fibromyalgia, HPA-axis dysfunction (“adrenal fatigue”) or over training. (Source 2)

Risk Factors For Iron Deficiency

Inadequate iron intake from iron-rich foods will cause low iron status. While it’s possible to meet iron requirements from diet alone, it’s important to note that certain people or populations may have higher needs, especially growing children, those who menstruate and pregnant women. 

Risk factors to consider include:

• A history of blood loss. Blood loss is the main way that the body loses iron. Unlike other minerals, iron is not lost through sweat or urine. If we lose more blood than we can replace with iron in the diet, then we become deficient. Reasons for blood loss include:
• Menorrhagia, or heavy menstrual bleeding
• Blood loss or hemorrhage from childbirth
• Blood donation
• Surgery (Source 2)

• Celiac disease, which affects the ability of the small intestine to absorb nutrients, may be an underlying cause for poor iron absorption and the resulting deficiency. One study found 81 percent of participants with Celiac disease to be iron deficient. Other gastrointestinal conditions, such as H. Pylori infection or atrophic gastritis, may contribute as well. (Source 2, 4, 5)

• Vegetarian, vegan and other low-iron diets. Heme iron is more bioavailable and absorbable and only comes from animal foods such as grass-fed beef, bison, liver, bone marrow and shellfish. It may be more challenging to meet daily iron needs from plant foods alone that contain non-heme iron. 

Iron Deficiency In Pregnancy 

Iron needs increase in pregnancy from 18 mg per day for menstruating women to a Recommended Dietary Allowance (RDA) of 27 mg per day during pregnancy. (Source 6)

Iron requirements are similar to pre-pregnancy needs during the first trimester, but then ramp up in the second trimester and third trimester due to an increase in blood volume, the growth of the placenta and the needs of the developing baby. 

Because of these increased needs, pregnant women are more at risk for iron deficiency and related health problems. In addition, many women enter pregnancy in an iron-deficient state or have a hard time eating iron-rich foods during pregnancy because of nausea and food aversions. Blood loss during delivery also contributes to iron deficiency increased risk during the postpartum period. 

In a Canadian study of over 44,000 women, only about 60 percent of pregnant women received a ferritin test during pregnancy, leaving a full 40 percent who did not. Of those who received a ferritin test, 71 percent received the test at their first prenatal visit during the first trimester, before iron needs dramatically increase. (Source 7)

Women were likely to only receive the single ferritin test without follow up in the second trimester or later. Iron testing may be even less likely for those with a lower socioeconomic status. It’s also important to note that the women in this study did not need to pay out-of-pocket for ferritin testing, which many women may have to in the United States health care system, presenting a further barrier to proper assessment of iron levels. 

Of the women in the study who did have serum ferritin tested, 50 percent had low levels of ferritin and 25 percent had severe iron deficiency. (Source 7)

Such a prevalence of iron deficiency is concerning because iron deficiency in pregnancy is linked to negative outcomes for both mother and her baby, including: 

• Iron deficiency symptoms including fatigue and weakness
• Preterm delivery/preterm birth
• Low birth weight
• Postpartum depression
• Maternal death
• Neurodevelopmental delays (Source 7)

Because of how common iron deficiency is in pregnancy, it is important to include ferritin, the standard measure of iron deficiency, as a regular screening test in prenatal obstetrics care. It’s a matter of public health.

How To Reverse Iron Deficiency

Luckily, iron deficiency (with or without anemia) is quite easy to prevent and treat. Here are some action steps focusing on evaluation, diet and iron supplementation:

1. Know your iron status. Ask your provider for a full iron panel that includes ferritin along with any routine lab work. This is especially important before, during and after pregnancy when women are at high risk for low iron. During pregnancy, ask for a ferritin test in each trimester.


2. Optimize your diet by eating iron-rich foods daily. We discussed that heme iron sources, from foods like bison, beef and oysters is more easily absorbed than plant sources of iron, such as lentils and greens. To increase absorption or high iron plant foods, add a source of vitamin C, from either foods like citrus or a vitamin C supplement. 

   It may be helpful to use an online tracking tool (such as cronometer.com) to see if you are meeting your dietary iron needs. Or, for personalized guidance, especially if you eat a plant-based diet or are preparing for pregnancy, work with a functional medicine-oriented Registered Dietitian or another knowledgeable clinician. 

3. Consider iron supplements, only when needed. There are a couple downsides to iron. First, it’s important to supplement iron only as needed instead of routine iron supplementation for everyone. Too much iron in the body, or iron overload, is detrimental to health, especially since iron is stored and accumulates in the tissues, causing inflammation if not accessed for use. Second, many oral iron supplements are poorly tolerated, causing gastrointestinal symptoms such as nausea and constipation. (Source 8) In some cases, intravenous iron may be required for higher dosages that bypass the GI tract. Intravenous iron is often harder to obtain than oral iron.  Third, please work with a qualified medical provider or registered dietitian to properly assess if your iron deficiency is in fact a copper deficiency. Your body has an iron recycling system, which ensures adequate iron is in constant circulation.  Ceruloplasmin, is the transporter made from copper and vitamin A and is necessary for iron to be converted into energy. When copper or vitamin A levels are inadequate, ceruloplasmin will be low and impact this system. It will appear on routine labwork that you are deficient in iron when it’s more complex than that – your body may need more balance in your minerals overall than over-supplementing with just one.

   Today, it is more common for high quality multivitamins, including prenatal vitamins, to also be iron-free so that each person may add iron only when needed and be able to adjust dosages.

   Core Med Science’s Liposomal Multivitamin with Active B Complex, Minerals and Antioxidants doesn’t contain iron for these reasons. 

Liposomal Iron Supplements

For those who actually do need to supplement with iron, liposomal iron supplements are a superior option. When iron is packaged in a liposome, a phospholipid membrane that mimics our own cells, supplemental iron absorption increases. (Source 9) This means that you may require a lower dose but get better results. 

Liposomal iron also solves the problem of gastrointestinal side effects because it is much better tolerated, especially for those with sensitive stomachs or with morning sickness that makes taking iron supplements more challenging. 

Core Med Science’s Liposomal Iron offers this superior absorption and tolerance. It is available in a convenient (and tasty!) liquid form so it’s easy to adjust the dose to your needs. Be sure to work with your doctor for proper dosing and monitoring. 

With 50 percent of pregnancies affected by iron deficiency, it is important to have regular ferratin screenings and supplement with liposomal iron in order to maintain optimal iron levels. 

 References

1. Short, M. W., & Domagalski, J. E. (2013). Iron deficiency anemia: evaluation and management. American family physician, 87(2), 98–104. Full text: https://www.aafp.org/afp/2013/0115/p98.html 
2. Soppi E. T. (2018). Iron deficiency without anemia - a clinical challenge. Clinical case reports, 6(6), 1082–1086. Full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986027/ 
3. Killip, S., Bennett, J. M., & Chambers, M. D. (2007). Iron deficiency anemia. American family physician, 75(5), 671–678. Full text: https://www.aafp.org/afp/2007/0301/p671.html  
4. Berry, N., Basha, J., Varma, N., Varma, S., Prasad, K. K., Vaiphei, K., Dhaka, N., Sinha, S. K., & Kochhar, R. (2018). Anemia in celiac disease is multifactorial in etiology: A prospective study from India. JGH open : an open access journal of gastroenterology and hepatology, 2(5), 196–200. Full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6207013/ 
5. Hudak, L., Jaraisy, A., Haj, S., & Muhsen, K. (2017). An updated systematic review and meta-analysis on the association between Helicobacter pylori infection and iron deficiency anemia. Helicobacter, 22(1), 10.1111/hel.12330. Abstract: https://pubmed.ncbi.nlm.nih.gov/27411077/ 
6. National Institutes of Health. Iron: Fact Sheet for Health Professionals. Retreived September 27, 2021 from https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/ 
7. American Society of Hematology. (2021, August 30). One in two pregnancies are affected by iron deficiency, yet many women don’t get a simple screening test to check. ScienceDaily. Retrieved September 27, 2021 from www.sciencedaily.com/releases/2021/08/210830104917.htm
8. Low, M. S., Speedy, J., Styles, C. E., De-Regil, L. M., & Pasricha, S. R. (2016). Daily iron supplementation for improving anaemia, iron status and health in menstruating women. The Cochrane database of systematic reviews, 4, CD009747. Abstract: https://pubmed.ncbi.nlm.nih.gov/27087396/
9. Baomiao, D., Xiangzhou, Y., Li, L., & Hualin, Y. (2017). Evaluation of iron transport from ferrous glycinate liposomes using Caco-2 cell model. African health sciences, 17(3), 933–941. Full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5656219/