Iron Supplements – Pregnancy, Postpartum And Menorrhagia
Iron is a nutrient that is critical for health and a well-functioning body, yet it is one of the most common nutrient deficiencies in the world. Why is this? For many, iron simply isn’t on the radar and we may think we are getting enough in the diet, but in actuality, it’s slowly being depleted.
If you are iron deficient or are experiencing the relentless fatigue of iron deficiency anemia, iron becomes critical to understand and address. Even better, let’s address iron before this happens. After all, prevention is the best medicine.
How much iron do I need? Can I get iron through food? What is the best iron supplement? I need to raise my iron levels, but my body isn’t tolerating the supplements my doctor prescribed. What do I do?
These are very common questions when it comes to iron and ones that I will dive into in this article.
Iron is a nutrient of particular importance for women during menstruation, pregnancy and the postpartum periods of life. Because of blood loss and increased iron needs, most women need to ensure they are getting enough.
In my years as an Anesthesiologist, I’ve been with women during labor and delivery of their babies, especially during Cesarean sections (C-sections). Nearly 1/3 of all deliveries is the US are by C-section according to the latest 2019 data.
One of my primary jobs during a C-section is to administer medications, including oxytocin or ergometrine, in order to limit the amount of blood loss from the uterus immediately after the baby has been delivered. Then, I work to aggressively replace the volume of blood lost with intravenous fluid administration to preserve hemodynamic stability.
Although blood loss during a C-section range between women, an average woman loses about 500 cc of blood. (Source 1) To put that volume in perspective, 500 cc would be about 11% the total amount of blood circulating in a 150 pound woman. You can see how this blood loss adds an additional stress to a new mother’s body, especially when it comes to the fatigue that ensues from not having enough hemoglobin, iron and therefore oxygen delivery to tissues.
Let’s dive in to understanding iron’s role in the body and action steps you can begin taking today in order to improve your iron levels.
In this article, you will learn more about:
- The mineral iron – importance for health and bioavailability
- Typical labs used to assess iron status
- Iron deficiency definition, symptoms, causes and treatment
- Iron deficiency during pregnancy and postpartum
- Menorrhagia definition, symptoms and treatment
- Dietary strategies to improve iron status
- Issues with iron supplements
- Liposomal iron for superior absorption and less side effects
All About Iron: Health Benefits, Bioavailability And Daily Needs
Iron is an essential mineral that we obtain through food in our diet. Iron is most famous for its role in making the hemoglobin protein in red blood cells that carries oxygen throughout the body. In fact, 75 percent of the iron in the body is found in red blood cells. (Source 2) Good oxygen transport is essential for energy production and the functioning of every cell. Low iron levels lead to low oxygen transport and all of the symptoms of iron deficiency that I will discuss, especially fatigue.
In addition to oxygen transportation, iron is found in the myoglobin of muscle tissue and as enzyme cofactors. Iron is important for mitochondrial function, where energy is created in all cells, along with protein and hormone synthesis, body temperature regulation, growth and development, maintaining connective tissues, thyroid health and immunity.
A newborn infant has about 250 mg of total iron in the body. This increases to around 3000 to 4000 mg for an adult male, but only 2000 to 3000 mg of iron in the body of an adult female. This difference may be attributed to lesser iron reserves in women, lower concentration of hemoglobin and a smaller vascular volume than men.
Of the total body iron, approximately two-thirds are utilized as “functional iron” such as that in hemoglobin (60%), myoglobin (5%) and various heme and nonheme enzymes (5%). The remainder is found in the storage forms of iron called ferritin (20%) and hemosiderin (10%). (Source 3)
So as you can see, good iron status is key.
There are two types of iron found in food: heme, from animal foods and non-heme from plant foods. Heme iron is better absorbed and more bioavailable so iron from animal food sources is much easier to absorb than vegan sources. It is estimated that 23 percent of heme iron is absorbed, compared to 2 to 20 percent of non-heme. The bioavailability of iron from a vegetarian diet, consisting of only non-heme iron, is only around 5 to 10 percent. (Source 4)
Iron regulation in the body happens at the site of absorption, with the hormone hepcidin. When iron status is good, the hepcidin decreases and the body absorbs less iron and when iron status is low, the hepcidin increases leading to more iron absorption. (Source 5)
This level of regulation is important for two reasons. First, iron isn’t readily excreted by the body. The only way to get rid of iron is through the sloughing of dead cells and bleeding. And second, too much iron is pro-inflammatory and causes tissue damage.
Once iron is absorbed into the body, it is transported by a protein called transferrin and carried to all tissues. Ceruloplasmin is another protein that plays a role in iron transport. This carrier also needs the mineral copperin order to effectively get the iron where it needs to go in the body.
These transporters carry the iron to the tissues, organs and bone marrow to make red blood cells. In addition, iron is transported to ferritin the storage molecule for iron which resides inside cells, and especially cells in the liver and brain. The body stores this iron for when intake might be low and the body needs more iron.
My main focus in this article is to talk about iron deficiency as this is what is important in the case of blood loss from C-sections that I discussed, pregnancy and in other cases, but it’s also important to note, that we don’t want too much iron in the body either. High levels of ferritin are very dangerous and might be due to a genetic condition where the regulation of iron absorption isn’t working (this is called hemochromatosis) or in a disease state the body may produce too much ferritin as an inflammatory response. In this state of iron overload, ferritin turns into hemosiderin, which you can think of as analogous to iron rusting. If this accumulates in the body it leads to all sorts of problems with organs, increasing the risk for infection or heart attacks. (Source 3)
The body doesn’t want too much iron or too little iron, like Goldilocks, it prefers to be just right and maintain iron homeostasis.
The Recommended Dietary Allowance (RDA), or the amount of iron recommended to get daily, for adult men and post-menopausal women is 8 mg per day. During the menstruating years, women need 18 mg per day to make up for monthly blood loss. During pregnancy, needs increase even more to 27 mg per day. (Source 2) These intakes account for the issues with iron absorption that I mentioned and will discuss more.
Functional Lab Ranges For Iron
Since most of the iron in the body is found in the blood, there are many blood markers that build a picture about iron status in the body. As a functional medicine doctor, I’m interested in not only the absence of disease, but truly optimizing health.
In the table below, I’ve included the lab ranges that you’ll typically see on your report, along with the functional ranges, which are a tighter range, representing more optimal values. (Source 6) It is possible to be within the lab range, but out of the functional range and still experience symptoms of iron deficiency.
Iron Deficiency Symptoms And Treatment
Now that we’ve covered some basics about iron metabolism and labs, you might be wondering: What is iron deficiency?
What are the symptoms of iron deficiency?
Iron deficiency will first show up as iron stores, measured as ferritin, decrease. As iron levels decrease, iron deficiency symptoms often begin to appear. These include:
- Restless leg syndrome
- Impaired cognition
Since iron is required for red blood cells to carry oxygen throughout the body, deficiency affects every cell and system, decreasing metabolism and energy.
Iron deficiency can lead to iron-deficiency anemia, which is when iron deficiency becomes so pronounced that the body can’t produce enough of the hemoglobin molecule that carries oxygen in your red blood cells. Anemia is diagnosed when hemoglobin values go below the lab range and coincide with the same symptoms, quite often fatigue.
Iron deficiency anemia, is the most common type of anemia worldwide. (Source 8) It is
also possible to have anemia because of a deficiency in vitamin B12 and/or folate, both of which are important for proper formation of red blood cells. In addition, anemias can occur because of poor production of red blood cells (aplastic anemia) or red blood cell destruction (hemolytic anemia) caused by autoimmunity.
What causes iron deficiency?
The most common cause of iron deficiency is simply inadequate intake of iron. You might not be eating enough iron-rich foods and not absorbing enough iron from them. Since you need more iron during periods of growth, young kids (6 months to 4 years old), growing adolescents, menstruating women, pregnant and postpartum women are more at risk for iron deficiency.
There are other causes to consider as well, including:
- Vegetarian and vegan diet choices. Since non-heme iron has lower absorption rates, it can be harder for plant-based eaters to meet their daily needs.
- Blood donation. Donating blood regularly lowers hemoglobin and ferratin levels and increases the risk of iron deficiency. (Source 9, 10)
- Celiac disease. Celiac disease is an autoimmune condition, triggered by eating gluten, which affects the enterocytes the line the small intestines and are responsible for the majority of nutrient absorption. When these cells become damaged, iron deficiency often occurs. In one study, 81 percent of participants with celiac disease had iron deficiency. (Source 11)
- Bariatric surgery. Iron deficiency is common in obesity and may exacerbate after bariatric, or weight loss, surgery. Gastric bypass may be particularly problematic as a cause of iron deficiency anemia. (Source 12)
- Inflammatory bowel disease (IBD). Those with ulcerative colitis and Crohn’s disease tend to have higher rates of anemia (Source 13), likely due to the blood loss through stool that is common with IBD flares.
- Gut infections. Gut infections may impact iron levels as well. pylori, a bacteria associated with stomach ulcers and cancer, is associated with lower iron levels and iron status improves with H. pyloritreatment. (Source 14)
What is the treatment for iron deficiency?
From my perspective, it is important to uncover the root cause of iron deficiency. Do you simply need to eat more iron-rich foods or is there another underlying factor affecting iron levels in the body? When we answer these questions, we can put a treatment plan into place to address the whole picture.
In addition to treating the root cause, iron levels can be restored through dietary approaches and iron supplements that I discuss more about below. It’s also important to monitor levels through blood work to make sure levels don’t become too high.
Before I get into the action steps you can start taking to improve your iron status, I want to discuss some key concerns regarding iron and pregnancy, postpartum and menorrhagia.
Low Iron In Pregnancy And Iron Deficiency Postpartum
Pregnancy and postpartum are such special times in a woman’s life, and a particularly critical time when it comes to iron levels. Iron deficiency anemia affects 22 percent of women in their childbearing years in developed countries and 50 percent in developing nations. (Source 15)
Iron needs increase throughout pregnancy and many women lack the stores of iron to support a full pregnancy. A main reason for the increased iron demand is the sheer increase in blood volume needed to support a pregnancy, grow the placenta and nourish a growing baby.
Interestingly, iron needs are not steady during pregnancy. Requirements may actually decrease during the first trimester, with the loss of menstruation, but rapidly increase in the second trimester as blood volume increases by 45 percent. (Source 16) In the third trimester, the baby has high iron needs for its own growth. Iron is essential for the brain and nervous system development. (Source 17)
Because of these increased demands, and often the challenges of eating enough iron-rich foods because of nausea, food aversions or diet choices, pregnant women are at a greater risk of developing iron deficiency and anemia during this time. (Source 18) In addition, good iron status helps to replenish blood loss during delivery to prevent iron deficiency postpartum.
Iron deficiency may affect the growth and development of the baby, and increase the risk for pre-term delivery, low birth weight and postpartum blood loss. In addition, inadequate iron during pregnancy is linked to increased cardiovascular risks for the baby later in life. (Source 18)
Iron supplementation is often recommended during pregnancy to improve pregnancy and birth outcomes. (Source 18) In fact, you’ll find most prenatal vitamins with iron for this reason. Studies show that iron supplementation during pregnancy helps to prevent iron deficiency anemia, but there may be associated side effects, including gastrointestinal symptoms. (Source 19, 20)
Truly the best iron supplement postpartum, is good iron status during pregnancy. Optimal iron status helps to replenish blood loss from delivery to prevent iron deficiency postpartum.
However, there may be some issues with iron supplementation during pregnancy. Iron supplements may trigger nausea and other digestive complaints. Women may even stop taking their prenatal vitamin because of these concerns, and therefore miss out on other nutrients. For the woman who has good iron status prior to conception, she might not need additional iron until later in her pregnancy.
I recommend using a prenatal vitamin without iron and then supplementing with iron as needed, per each woman’s individual needs as iron labs can be monitored throughout pregnancy. Liposomal iron in pregnancy may be better tolerated than the iron in prenatal or other iron supplements.
What Is Menorrhagia And What Are The Symptoms And Treatment
In addition to pregnancy and postpartum, menorrhagia is another time when a woman may be at higher risk for iron deficiency. What is menorrhagia? Menorrhagia is the medical term for heavy menstrual bleeding. This means that a woman’s period is either longer or heavier (or both) than normal, resulting in a greater blood loss. Menorrhagia is considered a bleeding disorder.
Menorrhagia affects 30 percent of women of reproductive age and is the leading cause of hysterectomy in women under 60. (Source 21)
Menorrhagia symptoms include:
- Heavy menstrual bleeding, such as bleeding through tampon or pad every hour, for several hours
- Bleeding for longer than 7 days
- Loss of more than 3 ounces of blood during a menstrual cycle
- Passing large blood clots, larger than a quarter
- Irregular bleeding between periods
- Iron deficiency or iron deficiency anemia secondary to blood loss
Determining menorrhagia causes requires peeling the layers away to get to the root of the issue. I want to ask why a woman has excess bleeding. Some common contributors are:
- Estrogen dominance. One role of estrogen is to build the uterine lining and high estrogen may build this up too much. Excess estrogen in the body can come from exposure to estrogen-like compounds found in the water, plastics and personal care products. High estrogen may also be the result of not effectively detoxifying estrogen so that it continues to circulate in the body.
- Endometriosis. This is a condition where the uterine lining grows outside of the uterus.
- Uterine fibroids. Fibroids, polyps or other growths in the uterus may contribute to menorrhagia.
- Anovulatory cycles. Cycles without ovulation contribute to estrogen dominance. Ovulation is needed for progesterone production and progesterone balances estrogen. Anovulatory cycles become more common during peri-menopause.
A heavier menstrual flow is associated with anemia. (Source 22) Because of this, anyone with menorrhagia should be evaluated for iron deficiency and we want to not only address the root causes, but also restore iron status.
Let’s talk about how to do that.
How To Increase Iron Levels With Diet
In the functional medicine paradigm, I’m always thinking about food first. Using food as medicine is one of the best strategies for meeting your daily iron needs and maintaining a good status.
Here are the dietary tips and tricks to consider:
- Eat an iron-rich diet. The richest sources of heme iron, the most absorbable form of iron, are: liver, bone marrow, shellfish, grass-fed beef, bison, lamb and other red meats. Good plant sources, or non-heme sources, include beans, dark leafy greens, nuts and seeds.
- Pair plant foods with vitamin C. Vitamin C helps with the absorption of non-heme iron, (Source 23) so try some lemon squeezed on your spinach or tomatoes with your lentils. You can also supplement with vitamin C during a meal.
- Separate iron-rich foods from calcium-rich foods and supplements. Calcium can inhibit the absorption of iron. (Source 24) This timing may be key for improving iron status, while also maintaining good calcium status.
- Separate coffee and tea from high iron foods. The polyphenol compounds found in coffee and tea inhibit the absorption of iron. (Source 25)
- Include meat with meals. Even small amounts of iron-rich animal protein have been shown to increase iron absorption with a meal. Heme iron helps to improve non-heme iron absorption. (Source 26)
- Cook in cast iron to increase the amount of iron in a meal.
Can Liposomal Iron Liquid Help Me Correct My Iron Deficiency Without The Usual Side Effects?
If you are in a high-risk category or already deficient in iron, you may need to consider supplementation along with the dietary suggestions. Iron supplements have been shown to be effective for treating and preventing iron deficiency anemia. (Source 27) In addition, iron supplements help to improve antioxidant defenses and reduce oxidative stress in those with deficiency. (Source 28, 29)
Iron supplements should increase hemoglobin levels by 1g/dL every 2-3 weeks. After hemoglobin has normalized it takes several months for stores (ferritin) to replenish. (Source 7)
A major issue with iron supplementation is that many people don’t tolerate them well. Side effects of supplementation include:
- Constipation or diarrhea
- Abdominal pain
- Black, tarry stool (Source 27)
Excess supplementation may cause iron overload and contribute to hemochromatosis in genetically susceptible individuals.
Liposomal iron solves both the problem of poor absorption and the uncomfortable GI side effects in one fell swoop. Liposomal iron is transported into the body through a liposome, rather than the typical absorption method that requires the cells of the small intestine to take up iron-heme complexes whole by a process called endocytosis.
Liposomes are constructed much like a microscopic cell or sphere containing iron at its center surrounded by layers of phospholipids on the outside. The natural phospholipids forming the outside of the liposome are identical to the building blocks of our cell membranes. This allows liposomes to easily fuse with intestinal cells or be taken up whole.
This means absorption is higher from a liposome containing iron than a plain iron supplement. (Source 30)
Not only is the delivery fast and absorption high, this liquid iron supplement is also typically better tolerated, especially for those with sensitive stomachs, including pregnant women.
Typical supplementation for iron deficiency ranges from the RDA up to 45 mg per day, which is the tolerable upper limit (UL). These are often the levels found in prenatal vitamins as well. Those with iron deficiency anemia may be prescribed much higher doses, often up to 100 or 200 mg per day. Too much iron negatively impacts the body, so it is best to work with a provider and monitor iron levels as you go.
Lower dosages, typically around the RDA, can be taken regularly, especially for those at higher risk, such as vegetarians, pregnant women or others not meeting their needs through food alone.
I’m a fan of Core Med Science’s Liposomal Iron Supplement, which delivers iron as ferrous gluconate, packed in a highly absorbable non-GMO liposome. Each serving provides 5 mg of the daily needs. Remember that most iron from food and supplements isn’t very well absorbed. With this product, you’ll likely need a much lower dose of iron to meet your iron goals because it is highly absorbed. And without all that extra iron in the digestive system, this product is generally better tolerated than typical high dose iron supplements.
Since iron supplements may interact with certain medications, talk to your doctor before beginning any new supplement, especially if you take medications or have a medical condition.
Summary Of The Key Points You Learned Today:
- Iron is an essential mineral obtained through the diet.
- Iron’s main role is in the hemoglobin of red blood cells that transports oxygen throughout the body.
- There are two types of iron found in food: heme and non-heme. Heme iron (animal sources) is more absorbable.
- The recommendations for daily intake are 8 mg per day for men and post-menopausal women, 18 mg per day for menstruating women and 27 mg per day during pregnancy.
- Many common blood labs are used to assess iron status. Ferritin is the most sensitive marker for iron deficiency.
- Iron deficiency and iron-deficiency anemia are both common worldwide. The main symptom is fatigue.
- The main cause of iron deficiency is inadequate intake of iron.
- Iron is of particular concern during pregnancy because of increased needs and postpartum because of blood loss during delivery.
- Menorrhagia or heavy uterine bleeding is another cause of iron deficiency in women.
- Dietary strategies provide the foundation of meeting and restoring iron status.
- Iron supplements are poorly absorbed and cause gastrointestinal side effects.
- Liposomal iron is better absorbed and well-tolerated. In addition, lower dosages are needed for benefit.
By now you likely know more about iron than you thought possible! Whether you are vegetarian, planning a pregnancy, experiencing heavy periods or have another concern about your iron status, my hope is that you feel empowered to meet and maintain your iron needs, naturally, in order to feel your best.
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