Pregnancy The Science of Nutrition

Iron 101: A Guide to Pregnancy and Postpartum

Steph Greunke

Iron 101: A Guide to Pregnancy and Postpartum

Table of contents

  • Intro
  • Why Iron Is Needed How Much Is Needed?
  • What Type of Iron Is Optimal?
  • Why We Dosed Iron Separately Customize Your Dose For Your Needs
  • Symptoms of Low Iron
  • A Smarter Iron Supplement

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We’re excited to launch our prenatal Iron supplement as the latest addition to our lineup of highly-researched and thoughtfully formulated supplements for mamas and mamas to be. 

Why Iron is needed 

Iron is needed by both mama and baby through pregnancy and postpartum. Mama needs Iron for healthy blood and oxygen transport, which is particularly essential during pregnancy to support the increase in blood volume that all mamas experience. It also supports thyroid function, placenta development, and helps fight fatigue. Iron is needed in postpartum to help rebuild blood after loss from delivery and lochia (the normal phase of bleeding that can last weeks after delivery).

Baby needs Iron in-utero to support a healthy birth weight and on-time neurodevelopment. It is especially critical as the negative effects of low Iron on a baby can cascade into childhood. Low Iron stores in a newborn baby have been shown to increase the risk of subsequent Iron deficiency anemia which results in changes in energy metabolism in the brain and defects in neurotransmitter function and myelination. Infants with Iron deficiency anemia are at risk of developmental difficulties involving cognitive, social-emotional, and adaptive functions.

How much is needed?

The RDA for Iron increases from 18mg in adult women to 27mg in pregnant women due to the increased needs described previously.

The RDA for Iron actually plummets to 9mg for breastfeeding women, as it assumes breastfeeding women aren’t menstruating. However, this fails to take into account the loss of blood at delivery and through lochia. 

We recommend continuing to target 27mg Iron through diet and supplementation for at least the first 6 weeks of recovery to support blood rebuilding. After this time, a number of variables including ferritin (blood Iron) levels, breastfeeding status, dietary intakes, and whether or not your cycle has returned will influence your iron needs. We recommend getting testing at this stage to determine your current status and to inform your own personal needs. 

What Type of Iron is optimal?

Iron is found in both plants and animals. Animal sources of Iron (called heme Iron) include red meat, poultry, and fish. Plant sources of Iron (called non-heme Iron) include spinach, chard, lentils, chickpeas, quinoa, and pumpkin seeds. Heme Iron is absorbed by the body far better than non-heme Iron, so Iron deficiency can be common among those who limit red meat consumption. Pregnant women who are experiencing meat aversions may also struggle to obtain adequate Iron. Note that Vitamin C can increase the absorption of non-heme Iron.

It can be difficult for mamas to meet Iron requirements, particularly if they don’t eat much red meat, or if they have strong meat aversions during early pregnancy. If a supplement is needed, we recommend Ferrous Bisglycinate Chelate, a mineral chelate in which Iron is bound to two Glycine amino acids. We chose this form for our Prenatal Iron supplement as it is easily absorbed by the body and minimizes the constipation and gastric upset that is common with supplemental Iron.

Why we dosed Iron separately 

While many prenatal vitamins include large doses of Iron in their formulas, and others omit it entirely without any mention, our research led us to a different approach. Iron is critical for mamas and mamas to be, but too much can be just as dangerous as too little. Too little puts mama and baby at risk of anemia and developmental concerns, while too much supplemental Iron can generate oxidative stress and alter the gut microbiome. 

In addition, Iron can interact negatively with other nutrients and block absorption of certain nutrients like Zinc. Therefore, by dosing separately from our Prenatal Multi, we promote optimal absorption of all nutrients needed and reduce the risk of taking too much supplemental Iron.

Customize your dose for your needs

Due to the risk of taking both too little and too much Iron, it’s important to take only what you need. This is why we created smaller doses that can be taken individually or combined for a larger dose as needed. It also allows you to modify your dose based on what stage of pregnancy or postpartum you’re in, and by what your diet might look like at the time. Our plan makes it easy to layer on the specific amount of Iron you need to your prenatal supplement routine.

We recommend that you talk to your health practitioner about testing your Iron status before, during, and after pregnancy, and supplement if you are falling short. The chart on our Iron page can help you tailor your dosage to your needs. These suggested dosages reflect insights from women’s health practitioners that regularly test the nutrient and hormone levels of women before, during, and after pregnancy.

Symptoms of low Iron

If you haven’t had your blood Iron (Ferritin) levels checked recently, it’s helpful to be aware of some of the signs of Iron deficiency. They include extreme fatigue, weakness, pale skin, chest pain, fast heartbeat, shortness of breath, headache, dizziness, lightheadedness, cold hands and feet, inflammation or soreness of your tongue, brittle nails, and unusual cravings for non-food substances like ice or dirt.

A smarter Iron supplement 

Iron is important for both mama and baby during pregnancy and postpartum, but dosing just isn’t one-size-fits all. Our highly-absorbable and gentle formula is dosed in such a way to support optimal dosing for all mamas and mamas to be during all stages of mamahood.

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Steph Greunke, MS, RD, CPT, PMH-C

Stephanie Greunke is a registered dietitian that specializes in prenatal/postnatal nutrition, behavioral psychology, and holds additional certifications in perinatal mental health and fitness. She's a key contributor and advisor to Needed as well as Needed’s Head of Practitioner Relationships. Steph is the owner of Postpartum Reset, an online postpartum nutrition course, and the co-host of "Doctor Mom" podcast.