You're more tired than usual. The stairs feel steeper, and you get dizzy when you stand up too quickly. Could it be iron deficiency?

Iron deficiency is the most common nutritional deficiency in pregnancy. According to the WHO, up to 40 percent of pregnant women have low iron stores. Your body needs significantly more iron when you're pregnant — and it's important to know why and what you can do about it.

Why Do Pregnant Women Need More Iron?

During pregnancy, your blood volume increases by up to 50 percent. Your body produces much more blood to supply both you and the baby, and iron is essential for making new red blood cells.

Iron needs increase throughout pregnancy:

First trimester: Needs are roughly the same as before pregnancy
Second trimester: Needs begin to increase significantly
Third trimester: Iron needs are at their highest — the body requires about double the normal amount of iron

Iron is used to:

Make hemoglobin (the oxygen-carrying protein in red blood cells)
Supply the fetus with iron for its own blood production
Build up the baby's iron stores for the first months of life
Prepare the body for blood loss during delivery

The baby takes priority. Even if you have low iron stores, your body will ensure the baby gets the iron it needs. This means you're the one who feels the iron deficiency, not the baby — but severe iron deficiency can still affect the pregnancy.

Symptoms of Iron Deficiency in Pregnancy

Many symptoms of iron deficiency resemble common pregnancy complaints, which means many pregnant women dismiss them. Watch for these signs:

Common symptoms:

Unusual tiredness and exhaustion
Dizziness, especially when changing positions
Paleness in the face, lips, and nails
Headaches
Heart palpitations and rapid pulse
Shortness of breath with mild exertion
Difficulty concentrating

Less common symptoms:

Cold hands and feet
Cracks at the corners of the mouth
Brittle nails
Restless legs (tingling and restlessness in the legs, especially in the evening)
Pica — unusual craving to eat ice, soil, or chalk (rare, but a known sign)

Many of these symptoms are common in a normal pregnancy. But if you feel unusually tired or dizzy, mention it to your midwife or doctor so your iron levels can be checked.

Blood Tests and Iron Values

Routine blood tests are taken early in pregnancy (usually at the first prenatal appointment around weeks 8-12) to measure hemoglobin (Hb) and ferritin.

Hemoglobin (Hb):

Measures the oxygen-carrying protein in the blood
Normal value for pregnant women: above 11.0 g/dL in the first and third trimesters, above 10.5 g/dL in the second trimester
Below these values is considered anemia

Ferritin:

Measures iron stores in the body
Ferritin below 30 micrograms/L indicates low iron stores
Ferritin below 15 micrograms/L means iron stores are depleted

When are blood tests taken?

At the first prenatal appointment (weeks 8-12)
Check at weeks 28-32 (third trimester)
More frequently if values are low or risk factors are present

Hemoglobin naturally drops somewhat in the second trimester because blood volume increases faster than red blood cell production. This is normal and called physiological anemia. Your healthcare provider is aware of this and factors it into the assessment.

Pregnant woman choosing iron-rich foods

Iron-Rich Foods for Pregnant Women

Diet is the most important source of iron. There are two types of iron in food:

Heme Iron (from Animal Sources)

Heme iron is absorbed 2-3 times better than iron from plant sources. Good sources:

Red meat — beef, lamb, game (best source)
Liver — very iron-rich, but limit to a maximum of 1 serving per week due to high vitamin A content
Fish and shellfish — especially mussels, sardines, and tuna
Chicken and turkey — especially the dark meat (thighs)

Non-Heme Iron (from Plant Sources)

Absorbed less efficiently, but intake can be improved with vitamin C. Good sources:

Legumes — lentils, chickpeas, beans
Whole grains — oatmeal, whole wheat bread, quinoa
Green leafy vegetables — spinach, kale, broccoli
Nuts and seeds — pumpkin seeds, cashews, sesame seeds
Dried fruit — apricots, raisins, prunes
Eggs

Tips for Better Iron Absorption

Iron absorption from food can be significantly affected by what you eat alongside iron-rich foods:

Increases absorption:

Vitamin C — drink a glass of orange juice with your meal, or eat bell peppers, broccoli, or strawberries
Meat — heme iron in meat increases absorption of plant-based iron in the same meal
Acidic food — citrus, tomato, vinegar

Inhibits absorption:

Coffee and tea — tannins bind iron. Wait at least 1 hour after a meal
Milk and dairy products — calcium inhibits iron absorption. Avoid drinking milk with iron-rich meals
Whole grains in large amounts — phytic acid binds iron (but whole grains are still recommended for fiber!)

Simple rule: Start dinner with something containing vitamin C (a piece of bell pepper, tomato in the salad, lemon over the fish), and wait with coffee until at least one hour after the meal.

Iron Supplements During Pregnancy

According to medical guidelines, iron supplements are recommended for pregnant women with low iron stores, but not routinely for everyone.

Who Should Take Iron Supplements?

Pregnant women with ferritin below 30 micrograms/L
Pregnant women with hemoglobin below 11.0 g/dL
Pregnant women with risk factors (vegetarians, short interval between pregnancies, twin pregnancies, heavy menstrual bleeding before pregnancy)

Recommended Dose

Preventive: 40-60 mg elemental iron daily if ferritin is between 15-30 micrograms/L
Treatment: 100-200 mg elemental iron daily if ferritin is below 15 micrograms/L or Hb below 10.5 g/dL
The dose is adjusted by your doctor or midwife based on your blood test results

Tips for Taking Iron Supplements

Iron supplements are known for causing side effects, but there are steps that can help:

Take the supplement on an empty stomach for best absorption (in the morning, 30 minutes before breakfast)
Take with vitamin C — a sip of orange juice or a vitamin C tablet
Avoid milk, coffee, and tea near the iron tablet
For heartburn: Try taking the tablet with a little food, even though absorption is somewhat reduced
For constipation: Increase fiber intake, drink plenty of water, and talk to your doctor about switching preparations

Never take more iron than recommended without speaking to your doctor. Too much iron can cause side effects and is not beneficial for the body. The dose should always be based on blood test results.

Common Iron Supplements

Slow Fe — slow-release iron tablet
Ferrous sulfate — common prescription form
Floradix — liquid iron supplement, often better tolerated but lower iron content
Nature Made Iron — widely available over-the-counter option

Talk to your doctor or midwife about which preparation is best for you.

Who Is Most at Risk for Iron Deficiency?

Some pregnant women have higher risk than others:

Pregnant women who were anemic or had low iron stores before pregnancy
Pregnant women with a short interval between pregnancies (under 2 years)
Pregnant women carrying twins or multiples
Vegetarians and vegans
Pregnant women with severe morning sickness that makes eating difficult
Pregnant women with chronic conditions that affect iron absorption

Consequences of Untreated Iron Deficiency

Mild iron deficiency mainly causes discomfort for you as a pregnant woman, but severe iron deficiency anemia can have consequences:

For you:

Increased fatigue and reduced quality of life
Dizziness and increased risk of falls
Increased risk of complications if you lose a lot of blood during delivery
Longer recovery time after birth

For the baby (with severe anemia):

Increased risk of preterm birth
Low birth weight
Low iron stores in the baby after birth

Moderate iron deficiency that is detected and treated during pregnancy rarely causes complications. The important thing is that it's caught — and that's what prenatal blood tests are for.

Pregnant woman preparing a healthy meal with iron-rich food

Frequently Asked Questions

Can I prevent iron deficiency during pregnancy?

Yes, a varied diet with iron-rich foods is the most important step. Eat red meat 2-3 times a week, include legumes, whole grains, and green vegetables daily, and combine with vitamin C for better absorption. Your healthcare provider will monitor iron levels with blood tests and recommend supplements if diet alone isn't enough.

Is it dangerous to take iron supplements without a doctor's recommendation?

Routine iron supplementation for pregnant women without documented iron deficiency is not recommended by most medical guidelines. Excess iron provides no benefits and can cause unnecessary side effects like constipation and nausea. Get a blood test first and let your doctor determine whether you need supplements.

Why do iron tablets cause constipation?

Iron preparations can slow bowel movements and make stool harder. Drink extra water (at least 1.5 liters daily), eat fiber-rich foods, and consider switching to a liquid iron preparation like Floradix, which is often better tolerated. Talk to your doctor if constipation is bothersome.

How quickly do iron supplements work?

You may start to notice improvement in energy levels after 2-4 weeks of iron supplements. Hemoglobin values typically rise noticeably after 4-6 weeks, but it takes 3-6 months to fully replenish iron stores. Don't stop treatment even if you feel better — follow your doctor's recommendation.

Follow your pregnancy week by week with our pregnancy guide. Here you'll find information about what's happening in your body, what your baby needs, and tips tailored to your week.

Iron Deficiency in Pregnancy: Symptoms, Food, and Supplements