Feeling worn out after having a baby is normal. But some of that exhaustion can be anemia, a shortage of healthy red blood cells, especially if your iron was low during pregnancy or you lost a lot of blood at delivery. Anemia after birth is treatable, and it’s worth asking about.
The short version
- What it is: not enough healthy red blood cells to carry oxygen through your body.
- Common causes: low iron and blood loss. ACOG names these as the two most common causes of anemia in pregnancy, and bleeding at delivery can add to it.
- Symptoms: tiredness, weakness, shortness of breath, a racing heart, pale skin, headache, and trouble concentrating. These overlap with new-baby exhaustion, so a blood test is the way to know.
- Testing: a blood count (hemoglobin) and a ferritin test, which shows your iron stores.
- Treatment: iron pills for most women. ACOG says IV iron should be considered if pills aren’t tolerated or don’t work.
- Get care right away for heavy bleeding, dizziness or fainting, or overwhelming tiredness, according to the CDC.
Why it happens
Iron deficiency and blood loss are the two most common causes of anemia in pregnancy, according to ACOG. Many women reach delivery with low iron already. About 10% to 16% of pregnant women in the U.S. have iron deficiency, and about 25% do in the third trimester, according to the NIH. Blood lost during delivery lowers your red blood cells further.
Low folate or vitamin B12 can also cause anemia, and they need different treatment. See Folic Acid and Anemia.
You’re more likely to be anemic after birth if you had anemia or low iron during pregnancy, lost a lot of blood at delivery, or have a condition that makes it hard to absorb iron, such as celiac disease, Crohn’s disease, or past stomach surgery. People who eat little or no meat may also run low, because iron from plants is absorbed less well, according to the NIH.
Symptoms
The NIH lists these signs of anemia:
- Tiredness and weakness
- Shortness of breath
- A racing or pounding heartbeat
- Pale skin
- Headache
- Trouble concentrating
- Feeling cold
Mild anemia can cause no symptoms at all. When it does, the signs can look like the exhaustion of caring for a newborn, so don’t talk yourself out of asking. If you feel far more tired than you expected, are short of breath doing small things, or feel your heart racing, ask for a blood test at your postpartum visit.
Testing
Your provider can check for anemia with a blood count, which measures hemoglobin, and can add a ferritin test to see how much iron you have stored. See Iron Levels in Pregnancy: Tests and What Your Results Mean.
The cutoffs aren’t the same for every clinic or study. Trials of postpartum anemia have often used a hemoglobin below 12 g/dL, and treatment plans vary by how low your level is, so ask what your numbers mean for you.
Treatment
Iron pills. For many women, the first step is an iron supplement taken by mouth. Both oral and IV iron work to rebuild iron stores after birth, according to ACOG’s 2021 bulletin on anemia in pregnancy. The usual downsides of pills are nausea, constipation, and diarrhea. See Prenatal Vitamin Side Effects and Iron Supplements in Pregnancy.
How long it takes. For most people treated for iron deficiency anemia, blood counts return to normal after about 2 months of iron treatment. Providers often keep going longer, up to 6 to 12 months, to rebuild the iron stored in the bone marrow, according to MedlinePlus. Your provider will decide how long is right for you and when to recheck your blood.
IV iron. ACOG recommends considering iron through an IV for women after the first trimester and after delivery who can’t tolerate oral iron or don’t respond to it. A review of 15 randomized trials with about 2,200 women found that hemoglobin was almost 1 g/dL higher 6 weeks after delivery with IV iron than with iron pills, and that pills caused more stomach side effects. IV iron more often caused skin flushing. The review’s authors said IV iron is a reasonable option for postpartum iron deficiency anemia. See the review in PubMed Central.
Folate or B12. If your tests show low folate or B12 instead of, or as well as, low iron, you’ll need treatment for those too. Large amounts of folic acid can hide B12 deficiency, so don’t treat suspected anemia yourself. See Vitamin B12 Deficiency.
Breastfeeding and iron
Your daily iron need drops from 27 mg in pregnancy to 9 mg while you breastfeed, partly because most women don’t have periods during that time, according to the NIH. That 9 mg is for women who aren’t low. If you’re anemic, your provider will recommend more, so don’t use the 9 mg figure to decide on your own whether to take iron. See Prenatal Vitamins While Breastfeeding.
When to get care right away
Some problems after birth are emergencies, and they can happen up to a year after delivery. The CDC says to get medical care immediately if you have:
- Heavy bleeding, soaking through one or more pads in an hour
- Clots bigger than an egg, or passing tissue
- Dizziness or fainting
- Overwhelming tiredness
- A headache that won’t go away or gets worse, or changes in your vision
- Swelling, redness, or pain in a leg or arm
- Thoughts about harming yourself or your baby
Tiredness alone isn’t an emergency, but tiredness that overwhelms you, especially with dizziness, a racing heart, or shortness of breath, is a reason to call. If you feel very down or overwhelmed, the National Maternal Mental Health Hotline is free and confidential, 24 hours a day, at 1-833-TLC-MAMA (1-833-852-6262).
What to do now
- If you had anemia in pregnancy or heavy bleeding at delivery, ask for a blood count and ferritin test at your postpartum visit.
- If you’re prescribed iron, take it as directed and tell your provider about side effects instead of stopping.
- Ask when your blood will be rechecked.
- Know the warning signs above, and have someone at home who knows them too.
Related reading
- Iron in Pregnancy: How Much You Need and How to Get Enough
- Iron-Rich Foods for Pregnancy and How to Absorb More
- Iron-Rich Meals and Snacks for Pregnancy: Easy Ideas
- Craving Ice While Pregnant? It Could Be a Sign of Low Iron
Sources
- Anemia in Pregnancy: Practice Bulletin No. 233, American College of Obstetricians and Gynecologists, 2021 (causes, oral and IV iron)
- Dietary Supplements and Life Stages: Pregnancy, NIH Office of Dietary Supplements, updated October 2026 (iron deficiency prevalence)
- Iron: Fact Sheet for Consumers, NIH Office of Dietary Supplements (symptoms, amounts, risk groups)
- Taking iron supplements, MedlinePlus Medical Encyclopedia, National Library of Medicine, reviewed July 2021 (how long treatment takes)
- Oral versus intravenous iron therapy for postpartum anemia: a systematic review and meta-analysis, PubMed Central, National Library of Medicine
- Urgent Maternal Warning Signs and Symptoms, Centers for Disease Control and Prevention (Hear Her campaign)
Updated November 2026. This article is for general information and is not a substitute for advice from your health care provider.
