Iron is a Big Deal!

There is so much to consider when it comes to nutrition and supplements during pregnancy, especially when it comes to keeping your iron levels up. Iron is crucial for making hemoglobin, a protein in the red blood cells that carries oxygen throughout your body and to your baby via your blood plasma, the largest component of your blood. When you don’t get enough iron through diet or supplements, your body makes fewer and smaller red blood cells. Less hemoglobin and fewer red blood cells can lead to anemia or iron deficiency.

What is Anemia?

During pregnancy, you hear a lot about being anemic but not so much about iron deficiency. Anemia is a pretty common experience during pregnancy, and it's something a lot of women talk about! You might hear conversations like, "Oh, I was anemic when I was pregnant!" "Same here!" or "I dealt with anemia through all my pregnancies and had to take iron supplements."

When a woman has anemia, it means she has insufficient healthy red blood cells (hemoglobin) to transport oxygen throughout her body effectively. This condition increases the risk of complications such as preterm birth, intrauterine growth restriction, postpartum hemorrhage, and other complications. Iron deficiency anemia, a specific type of anemia, carries the same risks, but in this case, the body's red blood cell reserve is reduced.

How Do I Know If I Have Low Iron?

You should receive adequate testing for anemia early in your pregnancy. It is part of the prenatal lab tests that are drawn. However, not all healthcare providers consistently follow up with re-testing or perform additional blood work to provide a more comprehensive overview of your health. Let's take a look at what tests you should have.

Early Pregnancy Testing

Most women see a healthcare provider in the first trimester of pregnancy and a entire slew of tests are ordered, including a Complete Blood Count (CBC), which checks your hemoglobin and other components of your blood. For iron, we are concerned about the CBC and ferritin levels.

1. Complete Blood Count (CBC)

The CBC is a standard test during pregnancy and includes several components. It checks your white blood cells for infection, your platelets for clotting, and your red blood cells for anemia.

Red Blood Cells

You have a bajillion more red blood cells than white blood cells - for every single white blood cell, there are roughly 600 to 700 red blood cells. It makes up about 40-45 percent of your blood volume.

The red blood cell count (RBC) measures the number and type of cells in your blood. Among them are:

• Hemoglobin - the concentration of red blood cells.

• Hematrocrit - the percentage of red blood cells

• Mean Corpuscular Volume (MCV) - the size of red blood cells

White Blood Cells

White blood cells are a little bit larger than red blood cells, but there are far few of them. They are crucial for fighting infection, viruses, and diseases.

Platelets

Platelets are very tiny, form in the shape of a plate, and are responsible for clotting your blood if you are bleeding. When actively clotting, they extend filaments that resemble a spider. These spidery legs make contact with a broken blood vessel to seal the damage and stop the bleeding. There are tens of thousands of platelets in just one drop of blood, and about one platelet per 20 red blood cells.

Red blood cells, white blood cells, and unactivated and activated platelets

2. Ferritin

What often gets overlooked with early testing is your ferritin levels. A standard Complete Blood Count (CBC) performed during pregnancy does not include a ferritin test. However, it can be done alongside the CBC to specifically screen for iron deficiency.

If your provider does not include a ferritin test, ask for one. A CBC alone is insufficient to detect early signs of iron-deficiency anemia. A ferritin test measures the body's iron stores, while the CBC assesses red blood cells, including hemoglobin. Both tests provide a more comprehensive overview of iron health, but most guidelines only require a CBC.

So, while hemoglobin carries and delivers oxygen throughout the body, ferritin is the storage unit that holds iron for later use. Think of the storage unit as a giant pile of sand at the beach that you are constantly dipping into when making a sand castle. You have just spent time collecting buckets of wet sand from the shoreline and hauling it past the water's edge to build your sand castle. The pile of damp sand is ferritin. The castle houses the hemoglobin. Or for those who do well with numbers, hemoglobin is the checking account and ferritin is the savings account. You need to make sure there’s enough savings to cover any incidentals.

Re-check the CBC and Ferritin

Not only is it essential to have your ferritin checked early in pregnancy, but it is also vital to have it rechecked around 24-28 weeks, along with a CBC. This is because your blood volume changes further along in your pregnancy in a process called hemodilution. Furthermore, you can have a normal hemoglobin level and have low ferritin, indicating iron deficiency anemia. Ferritin is considered the best measure of iron deficiency in pregnancy.

Hemodilution and Blood Cells

As your pregnancy progresses, your blood plasma volume expands. Plasma is the liquid component of blood that carries nutrients, hormones, red blood cells, and other elements throughout the body. The expansion is essential, as it supplies your growing baby with oxygen and nutrients and creates a vital reserve to replace blood lost during childbirth. The red blood cells transported in the plasma, however, do not increase. As a result, they become diluted. This is called hemodilution.

The first visual below does a great job of helping us understand hemodilution! Picture the red background as a big, beautiful red sea. The red blood cells start out clustered at the shore, where there are a lot of them. As they swim out further into the water (the blood plasma), they spread out and become more diluted in the vast ocean. It's a fun way to see how things change!

Low red blood count

When you have a low red blood cell count during pregnancy, it means the red blood cells are diluted because the blood plasma volume has increased. This is a normal occurrence, as your blood volume increases by 50 percent during pregnancy, but the number of red blood cells increases by only 30 percent. To manage this deficit, you need to eat foods high in iron and take an iron supplement.

Normal red blood count

Research shows that taking iron supplements leads to a substantial increase in hemoglobin concentration in the blood. This effect is significant in women with anemia, as elevated hemoglobin levels can improve overall oxygen transport.

High red blood count

A high red blood cell count, known as polycythemia, indicates that the blood is thickened due to an excess of cells. This condition may be a sign of dehydration and can also increase the risk of complications such as blood clots, growth restriction, or pre-eclampsia. Although it is uncommon, it is essential to monitor this condition closely.

Hemoglobin and Ferritin Levels

Hemoglobin

There are many components of the blood that have to be considered in relation to the hemoglobin, including ferritin, but hemoglobin during pregnancy normally ranges between 11 to 16 grams per deciliter (g/dL). A hemoglobin below 11.0 g/dl indicates anemia.

Ferritin

Different guidelines suggest widely varying levels for ferritin, ranging from the lowest minimum of 15 nanograms per milliliter (ng/mL) to the highest maximum of 130-150 ng/mL However, the consensus among many medical organizations is that anything below 30 ng/ml constitutes significant iron deficiency anemia meriting therapeutic treatment.

Recommended Intervention

Keep in mind that different providers, clinicians, and midwives will have their own protocols for intervention, but they will recognize that treatment is necessary at the following deficiency levels. Also, keep in mind that iron deficiency can occur regardless of your hemoglobin levels, which could be in the normal range or below normal.

Deficient	Ferritin	Hemoglobin	Recommended Intervention
Severe iron deficiency anemia	< 15 ng/mL	<10 g/dL	Therapeutic iron needed.
Significant iron deficiency	15-30 ng/mL	< 10.5 to 11 or > 11 g/dL	Eat an iron rich diet, consider nutritional counseling, and take iron to treat iron deficiency as recommended by your provider.

Prevention - Ferritin Levels in Early Pregnancy

While a ferritin level above 30 is considered "normal" in the first trimester of pregnancy, moderate iron stores (30-50 ng/mL) may indicate the need for iron supplementation, which will help you to meet the increased blood volume demands during pregnancy.

Talk to your provider about taking an iron supplement, such as Mega Food Iron Blood Builder, Floridix Iron and Herbs, Thorne Advanced Iron Complex, or Hemaplex for the prevention of anemia or iron deficiency. Ensure you are not caught off guard weeks later when you find out your hemoglobin and ferritin levels have dropped way below normal due to hemodilution. Studies show that women who supplement early in pregnancy with iron experience far less anemia and iron deficiency by the 27th week of pregnancy than those who do not.

Moderate	Ferritin	Hemoglobin	Recommended Intervention
Moderate range	30-50 ng/mL	10.5 to 11 +	Eat an iron rich diet and take iron as recommend by your provider to prevent iron deficiency.

Optimal Levels of Ferritin

Optimal ranges vary widely. Some providers consider ferritin at 50 ng/mL as a normal range, while others feel it should be higher, up to 70-80 ng/mL or more. The upper range for non-pregnant women is 150 ng/mL.

Optimal	Ferritin	Hemoglobin	Recommended Intervention
Optimal range	50-80 ng/mL	>11	Eat an iron rich diet and take the recommended daily intake of iron for pregnancy or as recommended by your provider.

High Ferritin Levels

Although high ferritin levels are uncommon, Sarah Thompson highlights studies that indicate a correlation between elevated ferritin levels in the first trimester and an increased risk of hypertension, preeclampsia, and gestational diabetes, typically when levels exceed 80 ng/mL. Some research suggests that ferritin levels above 45 ng/mL in early pregnancy may heighten the risk of gestational diabetes, which becomes 2.4 times higher when levels surpass 80 ng/mL at 28 to 30 weeks of gestation.

What are Signs of Anemia?

Signs of anemia can be hard to distinguish from the normal symptoms of pregnancy, such as feeling tired. Talk to your provider if you are feeling particularly fatigued. If you notice signs, they can include:

• Feeling easily fatigued

• You may experience an unusually rapid heartbeat, particularly with exercise.

• Feeling dizzy or faint

• Feeling short of breath

• You may have difficulty concentrating

• Your skin may look pale

• You may experience leg cramps

• Insomnia

Risks Associated with Anemia

First Half of Pregnancy

Risks associated with low hemoglobin in the first half of pregnancy have been associated with preterm birth, low birth weight, and preeclampsia.

Second Half of Pregnancy

Risks associated with lack of hemodilution (constricted blood volume) in the second half of pregnancy have been associated with premature rupture of the membranes and preeclampsia.

Birth

Anemia significantly increases the risk of postpartum hemorrhage. There are several reasons for this increase:

• There is less oxygen reaching the uterine muscle tissue, which reduces the muscles’ ability to contract efficiently.

• Anemia contributes to impaired blood coagulation, so normal clotting may not happen as it should.

• Reduced blood viscosity, where fewer red blood cells (low hemoglobin) make the blood thinner, allowing blood to move more easily through vessels.  

• Reduced ability to compensate for the blood loss.

What Might Increase My Risk of Anemia?

• If you are a vegetarian or vegan.

• Insufficient dietary iron.

• Insufficient protein consumption. Protein helps increase your plasma.

• Insufficient or no iron supplementation.

• If you are vitamin D deficient. Vitamin D plays an important role in iron absorption.

• A multiple pregnancy (twins or triplets).

• Having two pregnancies closer together.

• If you had heavy periods before pregnancy, which increases the chance of being anemic. 

  
  

What Can I do to Increase My Iron Levels?

1. Take an Iron Supplement

The recommended daily intake (RDI) of iron during pregnancy is 27 mg, though most women need more. Many prenatal vitamins contain 27 mg of iron, which may be sufficient for women with optimal lab values. However, some prenatal vitamins contain no iron. Always check the label. If no iron is listed or if it is less than 27 mg, take an additional iron supplement. There are many options for iron supplements, offered in pill or liquid form. They can easily be purchased over-the-counter or online.

2. Discuss Your CBC and Ferritin Levels With Your Provider

It is imperative to discuss your lab values with your provider. Make a plan for sufficient iron supplementation that meets your unique needs. Your provider may suggest higher doses if your anemia is severe or may offer another treatment plan, such as getting iron through an IV. When planning an out-of-hospital birth, anemia unresponsive to treatment may require consultation with a physician.

3. Eat Iron Rich Foods

Foods Rich in Iron

There are two types of dietary iron: 1) heme comes from animal sources, and 2) non-heme comes from plant sources. These two varieties make it fairly easy to identify which sources of iron you mainly consume. However, dietary iron is not created equally.

Heme Foods 

Heme foods are an excellent source of iron, which include: beef, liver, chicken, fish, pork, turkey. Heme foods have an excellent absorption rate. Your body utilizes between 15 to 35 percent of the heme food you consume.

Non-Heme Foods

Compared with heme iron, non-heme iron is less efficiently absorbed, at a rate of 2 to 20 percent. Non-heme foods include: raisins, apricots, bananas, beans, lentils, oats, seeds, grains, fortified foods, dark leafy greens and, vegetables such as broccoli, bok choy, beets, and Brussel sprouts. Seaweeds, such as dulse, nori, kelp, wakame, ogonori, and kombu are good sources of iron. 

If you are eating non-heme sources of iron only, you probably need to take a supplement.

What Increases the Absorption of Iron?

Pair vitamin C with both heme and non-heme foods: Consuming heme and non-heme rich foods combined with sources of vitamin C (like citrus fruits, peaches, papayas, sweet red peppers, berries, broccoli, and peas) will increase iron absorption. In order to absorb non-heme foods well, you need to eat significant quantities combined with a vitamin C supplement or foods rich in vitamin C. 

Vitamin C: Take 500 mg of vitamin C with your iron to enhance absorption.

Calcium: DO NOT take a calcium supplement or eat foods rich in calcium, as calcium inhibits iron absorption. Calcium is found in foods such as milk, yogurt, cheese, sardines, canned salmon, tofu, broccoli, almonds, fortified cereals, figs, turnip greens, and rhubarb.

Coffee, cocoa, and black tea: These beverages and food are major inhibitors of iron.

Eggs:  Eggs significantly reduce the absorption of iron. 

Fruits and Nuts: Fruits such as apples, blackberries, raspberries, and blueberries all have the ability to inhibit iron absorption.

Questions

If you have any concerns or questions after reading this blog post, talk to your provider. If it helps, write your questions or ideas down and bring them with you to your next appointment

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