Low Hemoglobin (Hb) or hematocrit (Hct) is defined as less than the 5th percentile of the distribution of Hb concentration or Hct in a healthy reference population based on age, sex, and stage of pregnancy (1).

Cut-off values are provided on the next page, based on the levels established by the Centers for Disease Control and Prevention (CDC).

Values by Status

	Non-Smoking	Any smoking up to 20 cigarettes/day	Smoking 21 to 40 cigarettes/day	Smoking > 40 cigarettes/day
Status	Hgb & Hct	Hgb & Hct	Hgb & Hct	Hgb & Hct
PG 1st trimester	11.0 & 33.0	11.3 & 34.0	11.5 & 34.5	11.7 & 35.0
PG 2nd trimester	10.5 & 32.0	10.8 & 33.0	11.0 & 33.5	11.2 & 34.0
PG 3rd trimester	11.0 & 33.0	11.3 & 34.0	11.5 & 34.5	11.7 & 35.0
PP, BF: 12-14 years	11.8 & 35.7	12.1 & 36.7	12.3 & 37.2	12.5 & 37.7
PP, BF: 15-17 years	12.0 & 35.9	12.3 & 36.9	12.5 & 37.4	12.7 & 37.9
PP, BF: 18 years & older	12.0 & 35.7	12.3 & 36.7	12.5 & 37.2	12.7 & 37.7

Status	Age	Hct. %	Hgb., Grams
Infant	5-12 months	33.0	11.0
Child	12-24 months	32.9	11.0
Child	24-60 months	33.0	11.1

Participant Category and Priority Level

Category	Priority
Pregnant Woman	1
Breastfeeding Woman	1
NonBreastfeeding Woman	6
Infants	1
Children	3

Justification

Hemoglobin (Hb) is the iron-containing, oxygen-carrying protein in blood. Hematocrit (Hct) is the percentage of blood that consists of packed red blood cells. Hb and Hct tests are used as an initial screen for anemia (2). There are many types of anemia, determining the specific type and cause of an individual’s anemia requires additional evaluation by a health care provider. Iron deficiency anemia (IDA), caused by inadequate iron, is the most common type of anemia (2). Megaloblastic anemia is a group of anemias usually caused by deficiency of folic acid or vitamin B-12 (3). Sickle cell and thalassemia are inherited types of anemia caused by abnormal red blood cells (4, 5). These are just a few of the types of anemia. Hb and Hct results allow WIC staff to identify participants who would benefit from further follow-up by their health care provider. Given that IDA is the most common type of anemia in children and women of childbearing age this write-up focuses on IDA. While neither a Hb nor Hct test are direct measures of iron status and do not distinguish among different types of anemia, these tests are useful screening tools for IDA (2).

Iron is present in all cells in the body and serves several vital functions. Iron is an essential component of Hb, a red blood cell that carries oxygen from the lungs to the rest of the body (2). Iron is involved in the synthesis of hormones as well as normal growth and development. Iron deficiency (ID) occurs when the body’s iron stores are depleted. ID may be caused by a diet low in iron, insufficient absorption of iron from the diet, increased iron requirements due to growth or pregnancy, or blood loss. Groups at risk of ID include: pregnant women, infants and young children, women with heavy menstrual bleeding, frequent blood donors, and people with cancer, gastrointestinal disorders or heart failure (2). ID progresses to IDA when iron stores become so low that hemoglobin production is disrupted. Changes in Hb concentration and Hct occur at the late stages of ID. IDA is associated with gastrointestinal disturbances, diminished physical work capacity, impaired thermoregulation, immune dysfunction, and Helicobacter pylori infection (6). There are additional risks associated with IDA in infants, children and pregnant women detailed below.

Iron in the Diet

Dietary sources of iron come in two major forms: heme and nonheme iron. Heme iron is well absorbed and found primarily in animal food sources, including red meat, liver, poultry, and fish. Nonheme iron is not as well absorbed and is found in foods from plants. Dietary sources of nonheme iron include iron-fortified grain products, legumes, fruits, and green leafy vegetables. Because nonheme iron is less bioavailable, the iron requirement for vegetarians is 1.8 times higher (7). Additional factors can also affect iron absorption. Consumption of vitamin C-rich foods and meat, fish or poultry increase the absorption of nonheme iron. Phytates, found in grains and beans, and some polyphenols, such as those found in cereals and legumes, can inhibit nonheme iron absorption (8). Calcium is linked to a reduction in the absorption of both heme and nonheme iron. The effects of enhancers and inhibitors on iron absorption are diminished by a typical mixed western diet and do not significantly impact most people’s iron status (2). Iron absorption, namely nonheme iron, is also dependent on an individual’s iron status. In a state of iron sufficiency iron absorption decreases, while absorption increases in a state of ID (8, 9).

Iron Deficiency Anemia in Women

Women of childbearing age require additional iron, when compared to male counterparts, to make up for blood loss during menstruation, increased needs during pregnancy and blood loss at delivery and postpartum. In addition to high iron needs, women often under consume iron putting this group further at risk for IDA (2). Additional risk factors for the development of IDA in pregnant women include: adolescent pregnancy, gestational diabetes and multiparity (10, 11). (For more information on adolescent pregnancy, gestational diabetes and multiparity see risk #331 Pregnancy at a Young Age, risk #302 Gestational Diabetes, risk #303 History of Gestational Diabetes and risk #335 Multi-fetal Gestation). The strongest predictors of IDA in postpartum women are IDA during pregnancy and high blood loss during delivery (12).

Pregnant women are at particular risk due to their increased iron needs. Pregnant women need almost twice as much iron as those who are not pregnant to support increased red blood cell production and the development of the fetus and placenta (13). The Recommended Dietary Allowance (RDA), the average daily level of intake sufficient to meet the nutrient requirements of nearly all (97%–98%) healthy individuals, for iron in pregnant women is 27 mg per day; the RDA for iron in non-pregnant women 14-18 years old and 19-50 years old is 15 mg and 18 mg respectively (7). Based on data from the National Health and Nutrition Examination Survey (NHANES), 2001-2014, the average iron intake from food for pregnant women aged 20 to 40 years was 17.2 mg, well below the RDA (14). Given the high iron requirements during pregnancy and insufficient intake from foods, iron supplementation is often recommended during pregnancy (2). Based on data from NHANES, 1999-2010, 16.3% of pregnant women 12-49 years old in the United States had ID, including 2.6 with IDA (15). Data also showed that ID was more prevalent in women in the second or third trimester, Mexican American pregnant women, non-Hispanic black pregnant women, and women with parity greater than or equal to 2.

In addition to the effects of IDA mentioned above, IDA during pregnancy is associated with several negative fetal and maternal outcomes. Maternal IDA increases an infant’s risk for low birth weight, premature birth, death, and impaired cognitive and behavioral development (2, 16, 17). IDA during pregnancy also increases the risk of maternal death (17). A long history of studies supported the belief that the fetus is protected from any impact of maternal iron status, however, a better understanding of regulation of iron physiology and neonatal iron status is challenging this assumption. Newer literature indicates fetal iron stores may be compromised when maternal iron stores are suboptimal, linking IDA during pregnancy with IDA in infants (16, 18, 19, 20, 21).

While the negative outcomes associated with IDA during pregnancy are well documented, additional research is needed to establish a clear causal relationship. IDA can also be a marker for food insecurity or lack of prenatal care, which can have similar effects (16). In a review of published reports, maternal iron supplementation has been shown to improve maternal iron status, however, the evidence is unclear on whether this increase leads to improvement in maternal and fetal health outcomes (17).

Iron Deficiency Anemia in Infants and Children

Infants and children are at risk for ID and IDA given their high iron requirements to support their rapid growth. The prevalence of anemia and possibly ID and IDA in infants and children has declined since the 1970s in the United States, and many attribute this decline to the fortification of infant formula and cereal and the establishment of the WIC program (22, 23). Based on data from the 2007–2010 NHANES 7.1% of children aged 1-5 were iron deficient and 1.1% had IDA (24). The rates of ID and IDA were higher in 1 to 2-year-olds at 13.5% and 2.7% respectively. There are no current national statistics regarding the prevalence of ID and IDA in infants before 12 months of age. Based on CDC recommendations, WIC regulations require a hematological test to screen for anemia during the following timeframes for infants and children (25):

Infants: 9 to 12 months of age.
Children 1-2 years: One blood test is required between 12 to 24 months of age, ideally 6 months after the infant screen (around 15 to 18 months of age).
Children 2-5 years: Once every 12 months for children 2-5 years of age whose blood test results were within the normal range at their last certification.

Iron is essential for normal neurodevelopment of infants and children. Numerous studies have linked IDA in infants and children to later adverse cognitive, motor and behavior effects (22). Cognitive deficits and the impact of IDA can be long lasting and may be irreversible, even with treatment (19, 26). It has been difficult to establish a causal relationship between IDA and these deficits due to confounding variables and difficulty in designing and executing the large-scale studies needed to demonstrate a direct link (22, 27). IDA can also increase susceptibility to lead poisoning by increasing intestinal lead absorption (22). (For more information on lead poisoning see Risk #211 Elevated Blood Levels).

While all infants and children are at risk of IDA due to their rapid growth, additional factors can place infants and children at higher risk. The table below outlines risk factors for IDA in infants and children:

Risk Factor	Additional Information
History of Prematurity*	Preterm infants miss out on the rapid accumulation of iron that occurs in the last trimester of pregnancy, are born with lower iron stores and are at risk of depleting their iron stores earlier than full term infants (22, 18, 26).
History of low birth weight or small for gestational age †	Low birth weight and small for gestational age infants are more likely to have lower iron stores that are unable to support the catch-up growth often seen in these infants (11, 18, 22).
Exclusive breastfeeding beyond 4 months of age without supplemental iron	While the iron breast milk contains is highly bioavailable, it is very limited. Full-term infants usually have adequate iron stores for 4 to 6 months but become at risk of developing iron deficiency at 6 to 9 months, unless they obtain adequate iron from complementary foods, iron-fortified formula or iron supplementation (11, 22).
Dietary habits linked with inadequate iron intake	The following dietary habits may increase an infant or child’s risk for inadequate iron intake: use of non-iron fortified formula, introduction of cow’s milk in the first year of life, weaning to whole milk or complementary foods that do not include iron-fortified cereals or foods naturally rich in iron (11, 22).
Maternal IDA	Infants born to mothers with IDA during pregnancy may be born with lower iron stores and are more likely to develop IDA as infants and children (22).
Feeding problems, poor growth, and inadequate nutrition ǂ	These challenges, which are often seen in infants with special care needs, are considered risk factors (22).
Demographic factors	Low socioeconomic status and having parents who are migrant workers or recent immigrants are also associated with increased risk (27).

* For more information on prematurity see Risk #142 Preterm or Early Term Delivery.

† For more information on low birth weight or small for gestation see Risk #141 Low Birth Weight and Very Low Birth Weight and Risk #151 Small for Gestational Age.

ǂ For more information on special care needs see Risk #362 Developmental, Sensory or Motor Disabilities Interfering with the Ability to Eat.

Implications for Minnesota WIC Nutrition Services

The objectives and intervention strategies are: To improve blood iron levels
To achieve and maintain normal dietary intake patterns
Assure regular care and follow-up with health care provider

The assessment should identify possible causes and/or contributing factors to low hemoglobin levels. Consider possible causes and/or contributing factors for low hemoglobin and tailor your assessment to these factors.

Participant Category	Possible causes and/or contributing factors for low hemoglobin values	Areas for Assessment
Pregnant Women	A woman’s blood volume doubles during pregnancy so there is an increased need for iron Nausea and vomiting can affect appetite and overall dietary intake Some women have difficulty accessing and/or tolerating prenatal vitamins. Plus, some prenatal vitamins do not contain iron, especially “gummy” vitamins Lead exposure Smoking Limited access to food Low dietary intake of foods rich in iron Medical conditions which cause blood loss or affect the woman’s ability to absorb iron	Is the woman experiencing nausea or vomiting? Skipping meals? Avoiding certain foods? Nausea and vomiting impairing desire or ability to cook? Is the woman consuming regular meals and snacks? Does her daily schedule with work/school interfere with eating regularly? Is the woman a vegetarian/vegan? Does the woman drink large amounts of sweetened beverages? Impacting overall diet quality? Does the family have food insecurity? Has a prenatal vitamin with iron been recommended by the health care provider? Does she have them? Does she take them, and if so, how often? Other medications or health concerns? Smoking, alcohol or drug use? Smoking increases the body’s iron requirement. Substance use can affect appetite and ability to prepare meals. Lead Exposure? Elevated lead levels increase the chances of iron deficiency by competing with iron absorption and by inhibiting production of red blood cells.
Breastfeeding and Non-Breastfeeding Postpartum Women	Limited access to food Low dietary intake of foods rich in iron Lead Exposure Medical conditions which cause blood loss or affect the woman’s ability to absorb iron	Is the woman consuming regular meals and snacks? Finding time to eat while caring for a newborn? Is the woman a vegetarian/vegan? Does the woman drink large amounts of sweetened beverages? Impacting overall diet quality? Does the woman consume excess milk? PICA? Does the family have food insecurity? Has a prenatal vitamin or another vitamin with iron been recommended by the health care provider? Does she have them? Does she take them, and if so, how often? Other medications or health concerns? Smoking, alcohol or drug use? Smoking increases the body’s iron requirement. Substance use can affect appetite and ability to prepare meals. Large blood loss during pregnancy? Is the woman receiving appropriate postpartum medical care and/or is the care scheduled? Lead Exposure? Elevated lead levels increase the chances of iron deficiency by competing with iron absorption and by inhibiting production of red blood cells.
Infants	Rapid growth Premature and/or low birth weight infants Born to mother who was anemic during pregnancy Exclusively breastfed infants not provided an iron supplement by 4 months of age Failure to introduce iron rich foods to the exclusively breastfed infant by 4-6 months of age Introduction of cow’s milk in infancy Failure to progress to more solids in later infancy. Lead exposure	Is the premature and/or low birth weight infant receiving regular medical care? Has the health care provider discussed the infant’s iron needs with the parents? Is the infant born to anemic mother evaluated for need for iron supplementation? Even infants born at term with normal weight may not have optimal iron stores if mother was iron deficient. Is the exclusively breastfed infant receiving an iron supplement? AAP recommends supplemental iron beginning at 4 months until adequate dietary iron is consumed for exclusively BF infants, may be especially important for breastfed infants born early or at low birth weight. Is the exclusively breastfed infant receiving a dietary source of iron by 4-6 months of age? Is parent familiar with age-appropriate dietary sources of iron? Is the older infant eating a varied diet with includes sources of iron rich foods? The American Academy of Pediatrics recommends introducing iron rich foods, such as meat and iron fortified cereal by 6 months of age. Is parent familiar with how to advance developmentally appropriate textures, including iron rich foods? Has cow’s milk been introduced? Early introduction of cow’s milk increases the likelihood of iron deficiency, both by displacing breastmilk or infant formula and through intestinal blood loss. Lead Exposure? Elevated lead levels increase the chances of iron deficiency by competing with iron absorption and by inhibiting production of red blood cells.
Children	Rapid growth Consumption of > 24 ounces of cow’s milk daily after age 1 year Low dietary intake of foods rich in iron Limited access to food Lead exposure Feeding disorders or issues related to preterm birth or low birth weight	Is the toddler or child “picky”? Eats lots of “junk food”? Avoids eating meat or only eats processed meats like hotdogs? Limited variety of foods? How much milk is being consumed? Is milk consumption > 24 oz? Is the child weaned from the bottle? Is milk replacing other foods? Does mom know how much milk is appropriate? Is the parent a vegetarian/vegan? Do they feed the toddler meat? What non-meat sources of iron do they eat? Does the family have food insecurity? This can contribute to Iron Deficiency Anemia. Is a referral needed? Does the child drink sweetened beverages? Has a vitamin with iron been recommended by the health care provider? Do they have them? Does the supplement have the recommended amount of iron? Many vitamins marketed to children do not iron, especially “gummy” vitamins. Do they take the supplement, and if so, how often? Have lead levels been tested? Normal? Other medications or health concerns? Children born premature or at low birthweight may have overt or subtle feeding difficulties such as oral aversions. Feeding difficulties may lead to anemia by decreasing the child’s ability and willingness to eat foods, especially iron rich foods such as meat and legumes. Growth pattern? Behavioral concerns? PICA

The Nutrition Counseling should incorporate the results of the assessment.

Participant Category	Nutrition Counseling
Pregnant Women	Manage nausea and vomiting. Eat small amounts frequently throughout the day. Eat food that are tolerated, avoid foods that increase nausea. Drink liquids between meals instead of with meals. For additional counseling recommendations, see risk code 301. Foods high in iron. Point out WIC foods that are high in iron, and discuss other foods that are good iron sources. Heme iron -- the type found in animal products such as red meat, fish and chicken -- is much better absorbed by the body, compared to non-heme iron (the type in plants). Eating a heme iron source with a non-heme iron source will enhance the non-heme iron absorption. Small quantities of meat in the diet can make a large contribution to important nutrients including iron, if accepted by the participant. Explore: What high iron foods the participant typically eats, and those they might consider trying, or eating more often. Food sources of Iron Minimizing foods that interfere with iron absorption. If the assessment identified large intake of foods that may adversely affect iron absorption such as coffee, tea and milk, explore whether the participant might be open to decreasing the quantity consumed and/or consuming these between meals. Tips for increasing iron absorption: Iron containing food + Vitamin C food combos. Offer simple doable tips such as eating WIC cereal as a snack with a small glass of WIC juice or a citrus fruit. Or eating a bean burrito with tomatoes for lunch. Food sources of vitamin C Overcoming barriers to taking iron supplements. Often Prenatal vitamins are recommended by health care providers. WIC can serve an important role in helping participants work through the barriers that may exist to taking the supplements consistently. Explore: Hesitations to taking the supplement Perceived side effects, such as constipation or increased appetite. Avoiding ingredients that may be in a tablet, such as gelatin, gluten or dyes. Preference for an over the counter multi-vitamin with iron (most gummies do not contain iron) Cost (may be covered by insurance, with a prescription) Ideas for remembering to take their supplement Place it in a visible place, but inaccessible to toddlers (can be poisonous) Set a recurring alarm on their phone
Breastfeeding and Non-Breastfeeding Postpartum Women	Eat regular meals and snacks. Assist mom with quick meal and snack ideas to fit into her busy schedule of infant care Foods high in iron. Point out WIC foods that are high in iron, and discuss other foods that are good iron sources. Heme iron -- the type found in animal products such as red meat, fish and chicken -- is much better absorbed by the body, compared to non-heme iron (the type in plants). Eating a heme iron source with a non-heme iron source will enhance the non-heme iron absorption. Small quantities of meat in the diet can make a large contribution to important nutrients including iron, if accepted by the participant. Explore: What high iron foods the participant typically eats, and those they might consider trying, or eating more often. Food sources of Iron Minimizing foods that interfere with iron absorption. If the assessment identified large intake of foods that may adversely affect iron absorption such as coffee, tea and milk, explore whether the participant might be open to decreasing the quantity consumed and/or consuming these between meals. Tips for increasing iron absorption: Iron containing food + Vitamin C food combos. Offer simple doable tips such as eating WIC cereal as a snack with a small glass of WIC juice or a citrus fruit. Or eating a bean burrito with tomatoes for lunch. Food sources of vitamin C Overcoming barriers to taking iron supplements. Often Prenatal vitamins are recommended by health care providers. WIC can serve an important role in helping participants work through the barriers that may exist to taking the supplements consistently. Explore: Hesitations to taking the supplement Perceived side effects, such as constipation or increased appetite. Avoiding ingredients that may be in a tablet, such as gelatin, gluten or dyes. Preference for an over the counter multi-vitamin with iron (most gummies do not contain iron) Cost (may be covered by insurance, with a prescription) Ideas for remembering to take their supplement Place it in a visible place, but inaccessible to toddlers (can be poisonous) Set a recurring alarm on their phone
Infants	Assure regular medical care for premature and/or low birth weight infants. Reinforce health care provider feeding recommendations. Breastmilk or infant formula until 1 year of age. Cow’s milk and plant based milks (e.g., soy, rice, almond milks) will not meet the nutritional needs of an infant. Foods high in iron. Exclusively breastfed infants need a dietary source of iron by 4-6 months of age. Iron-zinc fortified baby cereals or pureed/mashed meats are recommended as first solid foods for exclusively breastfed infants. In general, about 2 servings per day of cereal (2 tablespoons/serving or 1 to 2 ounces of meat per day is recommended to meet the need for iron and zinc. Assure iron supplements are used, if prescribed. AAP recommends supplemental iron beginning at 4 months until adequate dietary iron is consumed for exclusively BF infants. Supplementation may begin at 1 month for breastfed infants born early, depending on physician's evaluation of need. Introduction of complementary foods. Assist parent in making nutrient-rich choices for baby’s first foods. Encourage cup use and weaning from the bottle by 12-14 months of age to prevent over consumption of fluids, promote healthy appetite and encourage advancement of feeding skills.
Children	Foods high in iron. Point out WIC foods that are high in iron, and discuss other foods that are good iron sources. Heme iron -- the type found in animal products such as red meat, fish and chicken -- is much better absorbed by the body, compared to non-heme iron (the type in plants). Eating a heme iron source with a non-heme iron source will enhance the non-heme iron absorption. Small quantities of meat in the diet can make a large contribution to important nutrients including iron, if accepted by the participant. Explore: What high iron foods the participant typically eats, and those they might consider trying, or eating more often. Food sources of Iron >Minimizing foods that interfere with iron absorption. If the assessment identified large intake of foods that may adversely affect iron absorption such as coffee, tea and milk, explore whether the participant might be open to decreasing the quantity consumed and/or consuming these between meals. Tips for increasing iron absorption: Iron containing food + Vitamin C food combos. Offer simple doable tips such as eating WIC cereal as a snack with a small glass of WIC juice or a citrus fruit. Or eating a bean burrito with tomatoes for lunch. Food sources of vitamin C Overcoming barriers to taking iron supplements. Often Prenatal vitamins are recommended by health care providers. WIC can serve an important role in helping participants work through the barriers that may exist to taking the supplements consistently. Explore: Hesitations to taking the supplement Perceived side effects, such as constipation or increased appetite. Avoiding ingredients that may be in a tablet, such as gelatin, gluten or dyes. Preference for an over the counter multi-vitamin with iron (most gummies do not contain iron) Cost (may be covered by insurance, with a prescription) Ideas for remembering to take their supplement Place it in a visible place, but inaccessible to toddlers (can be poisonous) Set a recurring alarm on their phone

Provide referrals as necessary.

All participants with a hemoglobin level that meets the high-risk criteria (<10) should be referred to the health care provider for therapy and follow-up.
If the family has inadequate resources for purchasing food, refer to food assistance programs for which they may be eligible (e.g., SNAP, community food shelves, free/reduced school lunch program, soup kitchens, Fare Share)
Offer other referrals as deemed necessary, such as, drug and alcohol abuse counseling, smoking cessation programs, mental health services or counseling for eating disorders.

Best practice for WIC documentation for this risk code:

Document possible causes and/or contributing factors to low hemoglobin levels. Indicate plan for resolving low hemoglobin.
Document any referrals made to the health care provider or other resource

Additional Resources include:

Minnesota WIC Nutrition Modules – select the module Iron Deficiency Anemia in Women and Children
MN WIC Health Indicators Summaries by County, CHB and City
Iron – NIH Fact Sheet
AAP Clinical Report Diagnosis and Prevention of Iron Deficiency Anemia
CDC Recommendations to Prevent and Control Iron Deficiency Anemia
Iron Absorption Mechanisms--Harvard

Implications for WIC Nutrition Services

The WIC food package is designed to include foods that contain specific nutrients to improve the health status of program participants, address inadequate intakes, and, ultimately, prevent nutrient deficiencies such as ID and IDA. Nutrition education combined with the WIC food package can help decrease the likelihood that an individual would develop IDA.

For individuals who currently have low Hb or Hct, WIC staff can:

Refer participants to their health care provider for more thorough testing as appropriate. Only a health care provider can diagnose anemia and determine the specific type and cause.
Reinforce treatment plans, such as iron supplementation, provided by the health care provider, and refer participants to health care providers for medical follow-up care.
Per State policy, provide follow up testing/referrals at future appointments.
Discuss lead testing with participant or parent/caregiver and refer to appropriate resources if needed.
Reiterate infant feeding guidance such as providing iron-fortified infant formula for infants not breastfed or partially breastfed for the first year of life and offering iron-rich or iron fortified complementary foods around 6 months of age.
For breastfed infants, refer to healthcare provider to determine if iron supplementation is needed before 6 months of age, see:
- https://www.cdc.gov/breastfeeding-special-circumstances/hcp/diet-micronutrients/iron.html
Encourage consumption of iron-rich foods (with an emphasis on the foods in the WIC food package): Lentils and beans, fortified cereals, red meats, fish, and poultry, for more information, see:
- https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/#h3
Encourage consumption of foods rich in Vitamin C to aid in iron absorption: Citrus fruits, tomatoes, and other fruits and vegetables, for more information see:
- http://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/

Clarification

Basis for blood work assessment: For pregnant women being assessed for iron deficiency anemia, blood work must be evaluated using trimester values established by CDC. Thus, the blood test result for a pregnant woman would be assessed based on the trimester in which her blood work was taken.

Definition of Trimester: CDC defines a trimester as a term of three months in the prenatal gestation period with the specific trimesters defined as follows in weeks:

First Trimester: 0-13 weeks
Second Trimester: 14-26 weeks
Third Trimester: 27-40 weeks

Further, CDC begins the calculation of weeks starting the first day of the last menstrual period. If that date is not available, CDC estimates that date from the estimated date of confinement (EDC). This definition is used in interpreting CDC’s Prenatal Nutrition Surveillance System data, comprised primarily of data on pregnant women participating in the WIC Program.

References

1. Centers for Disease Control and Prevention [Internet]. Atlanta (GA): Centers for Disease Control and Prevention. Recommendations to prevent and control Iron deficiency in the United States. Morb Mortal Wkly Rep. 1998 Apr 3 [cited 2020 Apr 14];47(RR‐3):1-36. Available from: https://www.cdc.gov/mmwr/preview/mmwrhtml/00051880.htm.

2. National Institutes of Health [Internet]. Bethesda, MD: National Institutes of Health. 2020 Feb 28 [cited 2020 April 14]; [about 14 pages]. Available from: https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/#h6.

3. National Heart, Lung and Blood Institute health topics [Internet]. Bethesda (MD): National Institutes of Health (US). Pernicious Anemia; [cited 2020 Oct 20]. Available from: https://www.nhlbi.nih.gov/health-topics/pernicious-anemia.

4. MedlinePlus health topics [Internet]. Bethesda (MD): National Library of Medicine (US). Sickle Cell Disease; [reviewed 2018 Jun 7; updated 2020 Sep 16; cited 2020 Oct 20]. Available from: https://medlineplus.gov/sicklecelldisease.html.

5. MedlinePlus health topics [Internet]. Bethesda (MD): National Library of Medicine (US). Thalassemia; [reviewed 2016 Dec 16; updated 2020 Aug 24; cited 2020 Oct 20]. Available from: https://medlineplus.gov/thalassemia.html.

6. Clark SF. Iron deficiency anemia. Nutr Clin Pract. 2008 Apr 1 [cited 2020 Apr 24];23(2):128-141. Available from: https://onlinelibrary.wiley.com/doi/full/10.1177/0884533608314536.

7. Institute of Medicine Food and Nutrition Board [Internet]. Dietary Reference Intakes: The essential guide to nutrient requirements. Washington, DC: National Academies Press. 2006. [cited 2020 Apr 29]. Available from: https://doi.org/10.17226/11537.

8. Lynch S, Pfeiffer CM, Georgieff MK, Brittenham G, Fairweather-Tait S, Hurrell RF, et al. Biomarkers of nutrition for development (BOND)-iron review. J Nutr. 2018 Jun 1 [cited 2020 Sep 17];148(suppl_1):1001S-1067S. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6297556/.

9. Domellöf M, Braegger C, Campoy C, Colomb V, Desci T, Fewtrell M, et al. Iron requirements of infants and toddlers. J Pediatr Gastroenterol Nutr. 2014 Jan [cited 2020 April 30];58(1):119-129. Available from: https://journals.lww.com/jpgn/Fulltext/2014/01000/Iron_Requirements_of_Infants_and_Toddlers.28.aspx.

10. Cao C, O'Brien KO, Pregnancy and iron homeostasis: an update. Nutr Rev. 2013 Jan 1 [cited 2020 Apr 30];71(1):35–51. Available from: https://doi.org/10.1111/j.1753-4887.2012.00550.x.

11. Burke RM, Leon JS, Suchdev PS. Identification, prevention and treatment of iron deficiency during the first 1000 days. Nutrients. 2014 Oct 10 [cited 2020 Apr 30];10;6(10):4093-114. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210909/.

12. Milman, N. Postpartum anemia I: definition, prevalence, causes, and consequences. Ann Hematol 2011 Jun 28 [cite 2020 May 5] 90(1247). Available from: https://link.springer.com/article/10.1007%2Fs00277-011-1279-z.

13. Siu AL. Screening for iron deficiency anemia and iron supplementation in pregnant women to improve maternal health and birth outcomes: U.S. Preventative Task Force Recommendation statement. Ann Intern Med. 2015 Oct 6 [cited 2020 Apr 10]; 163(7):529-536. Epub: 2015 Sep 8. Available from: https://www.uspreventiveservicestaskforce.org/uspstf/document/RecommendationStatementFinal/iron-deficiency-anemia-in-pregnant-women-screening-and-supplementation#citation6

14. Bailey RL, Pac SG Fulgoni VL, Reidy KC, Catalano PM. Estimation of total usual dietary intakes of pregnant women in the United States. JAMA Netw Open. 2019 Jun 5 [cited 2020 May 8];2(6):e195967. Available from: https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2736174.

15. Gupta PM, Hamner HC, Suchdev PS, Flores-Ayala R, Mei Z. Iron status of toddlers, nonpregnant females and pregnant females in the United States. Am J Clin Nutr. 2017 Dec [cited 2020 Sep 23];106(6):1640S-1646. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5701724/

16. Means RT. Iron deficiency and iron deficiency anemia: implications and impact in pregnancy, fetal development, and early childhood parameters. Nutrients. 2020 Feb 11 [cited 2020 Apr 30];12(2):447. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7071168/

17. Peña‐Rosas JP, De‐Regil LM, Garcia‐Casal MN, Dowswell T. Daily oral iron supplementation during pregnancy. 2015 Jul 22 [cited 2020 Apr 30]. In: The Cochrane Database of Systematic Reviews [Internet]. London (UK): John Wiley & Sons, Ltd. C2015. Available from: https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004736.pub5/full.

18. Scholl T. Maternal iron status: relation to fetal growth, length of gestation, and iron endowment of the neonate. Nutr Rev. 2011 Nov 1 [cited 2020 Apr 10];69(1):S23–S29. Available from: https://academic.oup.com/nutritionreviews/article/69/suppl_1/S23/1815100.

19. Radlowski EC, Johnson RW. Perinatal iron deficiency and neurocognitive development. Front Hum Neurosci. 2013 Sep 23 [cited 2020 May 5];7:585. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3779843/

20. Abioye AI, McDonald EA, Park S, Ripp K, Bennett B, Wu HW, et al. Maternal anemia type during pregnancy is associated with anemia risk among offspring during infancy. Pediatr Res. 2019 Sep [cited 2020 May 5];86(3):396-402. Epub 2019 May 26. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6702090/.

21. Lee S, Guillet R, Cooper EM, Westerman M, Orlando M, Kent T, et al. Prevalence of anemia and associations between neonatal iron status, hepcidin, and maternal iron status among neonates born to pregnant adolescents. Pediatr Res. 2016 Jan [cited 2020 May 5];79:42–48. Available from: https://www.nature.com/articles/pr2015183#article-info.

22. Baker RD, Freer FR, and the Committee on Nutrition. Diagnosis and Prevention of Iron Deficiency and Iron-Deficiency Anemia in Infants and Young Children (0-3 Years of Age). Pediatrics. 2010 Nov [cited 2020 April 10];126(5):1040–50. Available from: https://pediatrics.aappublications.org/content/126/5/1040.long.

23. Cusick SE, Mei Z, Freedman DS, Looker AC, Ogden CL, Gunter E, et al. Unexplained decline in the prevalence of anemia among US children and women between 1988–1994 and 1999–2002. Am J Clin Nutr. 2008 Dec [cited 2020 May 6];88(6):1611–1617. Available from: https://doi.org/10.3945/ajcn.2008.25926.

24. Gupta PM, Perrine CG, Mei Z, Scanlon KS. Iron, anemia, and iron deficiency anemia among young children in the United States. Nutrients. 2016 May 30 [cited 2020 May 6];8(6):330. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4924171/. Corrected and republished from: Nutrients. 2017 Aug 15 [cited 2020 May 6];9(8):876. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579669/.

25. Special Supplemental Nutrition Program for Women, Infants and Children, 7 C.F.R. Sect. 246.7(e)(1)(i)(A) (2020). Available from: https://www.ecfr.gov/cgi-bin/text-idx?SID=4aee33ead8001dc4af3ab61a2ad506f8&mc=true&node=pt7.4.246&rgn=div5.

26. Lozloff B, Smith JB, Kaciroti N, Clark KM, Guevara S, Jimenez E. Functional Significance of Early-Life Iron Deficiency: Outcomes at 25 Years. J Pediatr. 2013 November [cited 2020 May 7];163(5):1260-1266. Available from: https://www.sciencedirect.com/science/article/pii/S0022347613005647?via%3Dihub.

27. Sui AL. Screening for iron deficiency anemia in young children: USPSTF Recommendation Statement. Pediatrics. 2015 Oct [cited 2020 Apr 10];136(4):746-752. Available from: https://pediatrics.aappublications.org/content/136/4/746.