22.  Screening for Iron Deficiency Anemia-Including Iron Prophylaxis

RECOMMENDATION

Screening for iron deficiency anemia using hemoglobin or hematocrit is

recommended for pregnant women and for high-risk infants. There is

insufficient evidence to recommend for or against routine screening for

iron deficiency anemia in other asymptomatic persons, but

recommendations against screening may be made on other grounds (see 

Clinical Intervention). Encouraging parents to breastfeed their infants and

to include iron-enriched foods in the diet of infants and young children is

recommended (see also Chapter 56). There is currently insufficient

evidence to recommend for or against the routine use of iron supplements

for healthy infants or pregnant women.

Burden of Suffering

Anemia is defined by the presence of a hemoglobin level that is below the

normal range of values for the population (see Accuracy of Screening

Tests).1-4 U.S. populations with a high prevalence of anemia include

blacks, Alaska Natives and Native Americans, immigrants from developing

countries, and individuals of low socioeconomic status.5-7 Anemia may be

due to a variety of underlying conditions. Iron deficiency is an important

cause among young children and women of reproductive age in the U.S.8-10

The prevalence of iron deficiency anemia in U.S. children has declined in

recent years6,11-14 and in 1993 was estimated to be at or below 3% for

children aged 1-5.15 In low-income populations and certain ethnic groups,

such as Alaska Natives, the prevalence of iron deficiency anemia in

children <5 years of age may be substantially higher, ranging from 10-30%

(unpublished data, Centers for Disease Control and Prevention, 1993).6

Among middle-class children, on the other hand, anemia is uncommon and

tends to be mild (i.e., within 1% of the hematocrit level defining

anemia).13,14 The exact prevalence of iron deficiency anemia among

pregnant women is uncertain, but national data suggest that <2% of

nonpregnant women aged 20-44 years have iron deficiency anemia.5

Among low-income, pregnant U.S. populations, a low hemoglobin level

and/or low hematocrit is present in 6% of white women and 17% of black

women during the first trimester and in 25% of white women and 46% of

black women during the third trimester.7 The high rates of anemia in

pregnant women may not be attributable to iron deficiency, however. In a

large cohort of urban, low-income, mostly minority pregnant women, only

12.5% of anemic women were iron deficient.16

As early as the 1960s, researchers demonstrated that, in general,

decreased hemoglobin alone does not have readily apparent adverse

effects unless it is below 10 g/dL (100 g/L).17-19 Clearly, persons with

markedly reduced hemoglobin levels are at risk for cardiopulmonary and

other complications. Reduced work productivity, endurance, and exercise

capacity have been associated with anemia or iron deficiency anemia in

adults, most of whom were from developing countries.20-26 Iron

deficiency and iron deficiency anemia during infancy and early childhood

have been associated with abnormal infant behavior, growth, and

development, although it is unclear how much of this association is

actually attributable to other factors often associated with iron

deficiency (e.g., poor nutrition, low socioeconomic status).27-35

Hemoglobin levels well below what is considered normal for pregnancy

have been associated with increased risk of low birth weight, preterm

delivery, and perinatal mortality.16,36-42

Accuracy of Screening Tests

The hemoglobin concentration and hematocrit are the principal screening

tests for detecting anemia. The World Health Organization hemoglobin cut-

points for diagnosing anemia in adults have been widely adopted: men, <13

g/dL; menstruating women, <12 g/dL; pregnant women, <11 g/dL.1 The

Centers for Disease Control and Prevention (CDC) has also produced

criteria for anemia: in infancy and childhood, <11 g/dL for 0.5-4.9 years

and <11.5 mg/dL for 5.0-11.9 years; in pregnancy, <11 g/dL during the first

and third trimesters and <10.5 g/dL in the second trimester.2 Studies have

shown that automated electronic cell counters and chemical analyzers

provide accurate and reliable data on red blood cell number and size and on

the concentration of hemoglobin.43,44 Although sampling of capillary

blood is more convenient in ambulatory practice and is especially useful

for infant testing, results obtained from capillary blood specimens are

less reliable than those from venous blood.45,46 One study found the

capillary microhematocrit to have a sensitivity of 90% and a specificity

of 44% when compared with values obtained from venous blood with an

automated cell counter.46

While sensitive for iron deficiency anemia, hemoglobin is not sensitive

for iron deficiency because mild deficiency states may not affect

hemoglobin levels.47 Hemoglobin is also nonspecific, since many cases of

anemia are due to causes other than iron deficiency.9,10,16 Reported

sensitivity of low hemoglobin for detecting iron deficiency ranges from

8-90% and specificity from 65-99% depending on the population, reference

standard and cut-point used.47-50 In a national sample, detection of a

hemoglobin <12 g/dL had a sensitivity of 90% and specificity of 78% for

iron deficiency in black women, whereas sensitivity and specificity were

36% and 95% in white women.50 Other tests (i.e., total iron binding

capacity, serum iron, transferrin saturation, erythrocyte protoporphyrin,

mean cell volume, red blood cell distribution width, and serum ferritin)

may be more accurate for the detection of iron deficiency, but they are

poor screening tests for iron deficiency anemia.48,51-59 Among these

tests, serum ferritin has the best sensitivity and specificity for

diagnosing iron deficiency in anemic patients.60

Effectiveness of Early Detection

Evidence is limited that in the asymptomatic general adolescent or adult

U.S. population, early detection and treatment significantly reduces

morbidity from anemia, iron deficiency, or the conditions that cause

them.17-19,61 This evidence is further limited by the fact that studies

often use inconsistent or vague definitions of anemia and iron deficiency.

Observational studies in developing countries have reported decreased

physical endurance and maximal exercise capacity in association with iron

deficiency anemia.21-24,26 The extent to which this might affect daily

activities that do not involve maximal exercise capacity is unknown.

Clinical trials and case series from developing countries have reported

conflicting results regarding a benefit of iron supplementation on work

productivity in anemic or iron-deficient workers.22,25,62-64 There is

little evidence evaluating adverse effects from the mild degree of anemia

that is most often detected by screening asymptomatic persons in

developed countries. In a Swedish cohort, anemic women (Hgb <12 g/dL)

reported no increase in reported infections, fatigue, or other symptoms,

but they were significantly more likely to report low work productivity

compared to nonanemic women.20 In a small, randomized placebo-

controlled trial of Welsh women with anemia (hemoglobin <10.5 g/dL)

detected by population-based screening, iron therapy did not result in

clinically or statistically significant improvements in psychomotor

function tests, symptoms, or subjective well-being, despite increased

hemoglobin concentrations.65 Trials evaluating the effects of iron

supplementation on physiologic outcomes such as running speed and

maximum running time in nonanemic, iron-depleted runners have been

inconclusive.66,67 Although the evaluation of anemia may disclose

underlying diseases (e.g., occult malignancies) that benefit from early

detection,68 there are no data to suggest that testing for anemia is an

effective means of screening for these conditions.

A number of trials have evaluated whether infants with iron deficiency

anemia benefit from early treatment. Randomized controlled trials have

demonstrated the efficacy of iron supplementation in correcting iron

deficiency anemia in infants and children, but its effect on clinical

outcomes is less clear.27,28,69,70 Four relatively large, generally well-

conducted, randomized controlled trials in developing countries have

evaluated the effects of iron supplementation on the behavior and

development of anemic infants.27,28,31,70 Three trials failed to show a

significant effect of treatment on standardized developmental test scores

after short-term (6-10 days) iron therapy.27,28,31 In one trial,31 an

additional 3 months of iron therapy for all infants corrected their anemia

but did not significantly improve developmental test scores. Another of

the trials27 reported that after 3 months of iron therapy infants whose

iron deficiency was completely corrected (36%) had developmental scores

similar to iron sufficient subjects, mainly because the scores of the

latter group declined. In the remaining 64%, treatment corrected anemia

but not iron deficiency, and test scores remained lower in this group. This

trial did not have a true placebo group, and other causes of anemia (such

as vitamin A deficiency) were not adequately excluded. There was no

delayed benefit of iron therapy in this trial; children with hemoglobin 10

g/dL as infants still had lower developmental scores at school entry 5

years later.33 The largest and most recent trial, which enrolled 12-18-

month-old infants with hemoglobins  10.5 g/dL, reported sizable,

statistically significant improvements in both mental and motor

development after 4 months of oral therapy.70 A small randomized

double-blind placebo-controlled trial71 in the United Kingdom evaluated 2

months of iron supplementation in urban, underprivileged toddlers (aged

17-19 months) with mild to moderate anemia, using the Denver

developmental screening test to assess outcome, which is not as well

stadardized or validated as the test used in the other trials. Effects on

developmental outcomes were inconsistent, but iron supplements

significantly increased rate of weight gain. Long-term results were not

evaluated. It is unclear why the results of these trials differ, although

adequacy and duration of therapy may account for some of the differences.

Clinical trials and a cohort study in older children have also demonstrated

improved iron and hemoglobin status with therapy,35,69,72 but evidence

for a clinical benefit from treatment of iron deficiency anemia is limited.

A double-blind randomized controlled trial in 1,358 9-11-year-old Thai

children failed to show any effect of iron treatment on intelligence test

scores in anemic children, despite the large sample size.73 A series of

small randomized controlled trials conducted in India did report small

improvements in IQ with iron treatment,74,75 however, and two small

randomized, controlled trials suggested a benefit of oral iron on some

tests of learning in anemic school-aged Indonesian children.76,77 All of

these studies suffered from important design limitations, such as use of

unvalidated tests, multiple significance testing, high dropout rates, and

addition of folic acid to the treatment regimen. Conflicting results have

been reported concerning the effect of iron supplementation on infection

rates in children.35,78-80 On the other hand, improved growth and weight

gain with 3-6 months of iron supplementation have been reported

consistently in placebo-controlled trials of anemic, malnourished children

in developing countries.34,35,81,82 Another controlled trial reported a

significant benefit from iron treatment on physical performance and

submaximal work capacity in anemic Indian boys.83 It is unclear whether

the results of these studies are generalizable to U.S. children, who are

likely to be healthy and otherwise adequately nourished.

Early detection and treatment of iron deficiency anemia in pregnancy has

been assumed to be beneficial because moderate to severe anemia (i.e.,

<9.0-10.0 g/dL) has been associated with a 2-3-fold increased risk of low

birth weight, preterm delivery, and perinatal mortality in numerous

cross-sectional and longitudinal observational studies in industrialized

countries.16,36-42,84 The consistency of these results across different

study designs and population samples is noteworthy, although such studies

do not conclusively prove that anemia directly influences pregnancy

outcomes. Many of the studies did not control for other factors that may

have had adverse effects (e.g., smoking, maternal malnutrition), or for

increases in hemoglobin and hematocrit that occur as gestation

approaches term; most did not differentiate iron deficiency anemia from

anemia due to other causes. A large body of data suggests that iron

supplements are effective in improving the hematologic indices of

pregnant women,85-91 but there is limited evidence that improving

hematologic indices in anemic women results in improved clinical

outcomes for the mother, fetus, or newborn. Most published trials

evaluating the effects of iron supplementation on pregnancy outcomes

systematically excluded anemic women (i.e., those with hemoglobins <10

g/dL or hematocrits 0.3) and are therefore not necessarily relevant to

pregnant women with iron deficiency anemia. They are described later in

the chapter (see Primary Prevention). One controlled trial enrolled Indian

women with hemoglobins as low as 7.0 g/dL who attended rural health

centers, randomizing the women by health center to receive either iron

and folic acid supplements for 100 days or no supplements.92 The trial

reported a significantly higher mean birth weight and lower rate of low

birth weight infants in women who completed 100 days of supplements

compared to controls. Among those receiving supplementation, the

increase in birth weight was significantly related to rise in hemoglobin. A

large (n = 601, retrospective cohort study from Kenya compared women

with severe anemia (hemoglobin 8.8 g/dL) who were or were not treated

with ferrous sulfate.93 Treatment was associated with markedly reduced

preterm delivery and stillbirth rates, and increased mean birth weight,

but there was no change in neonatal death rates. Women with "mild

anemia" (hemoglobin 8.9 g/dL) who received iron therapy before 30 weeks

also had lower preterm delivery and perinatal mortality rates compared to

those receiving no iron or iron after 30 weeks. Neither significance

testing nor adjustment for covariates was performed, limiting the

conclusions that can be drawn from these data. The detection of anemia

and the determination of its etiology may also lead to the discovery of

other correctable obstetrical risks (e.g., poor nutritional status, medical

illness) that might otherwise escape detection, but the effectiveness of

anemia screening in improving outcomes related to these risks has not

specifically been evaluated in developed countries.

Adverse effects of iron therapy include unpleasant gastrointestinal

symptoms (e.g., nausea and constipation) that are dose-related and, at

normal doses, reversible.94-97 Iron therapy can cause complications of

excessive iron storage in patients with an underlying iron storage

disorder (e.g., idiopathic hemochromatosis).98,99 A potential hazard of

iron supplements is unintentional overdosage by children in the home;

20,330 cases of ingestion of iron or iron-containing vitamins by children

under 6 years, including 3 fatalities, were reported to poison control

centers in 1993.100 Iron supplements accounted for 30% of fatal pediatric

pharmaceutical overdoses occurring between 1983 and 1990.101 Other

potential adverse effects of iron mentioned in the literature (e.g., birth

defects, cancer, heart disease, infection, metabolic imbalances of other

minerals, and harmfully high hemoglobin levels)109 have not been proven.

Primary Prevention (Iron Prophylaxis)

Studies of the effects of iron fortification of formula and cereal on

healthy, nonanemic infants have focused primarily on laboratory rather

than clinical outcomes. Randomized and nonrandomized controlled trials,

observational studies, and time series studies have demonstrated

substantial reductions in the incidence of iron deficiency and iron

deficiency anemia in healthy infants fed iron-fortified formula, iron-

fortified cereal, or breast milk (with iron-fortified cereal added at 4-6

months), compared to infants fed cow's milk or unfortified

formula.12,102-107 Evidence is more limited regarding clinical benefits

from iron fortification of infant diets. A cohort study reported that

infants fed iron-fortified formula beginning at age 6 months had

significantly fewer diarrheal episodes compared to infants fed whole

cow's milk (0.16 vs. 0.30 per child in the second 6 months of life); the

incidence of other medical conditions (e.g., otitis media, dermatitis,

wheezing) did not differ.106 This study did not have standardized criteria

for diagnosing medical conditions and had limited control for potentially

confounding variables, however. A controlled trial randomized healthy

infants at a mean age of 1.3 months to either iron-fortified or

nonfortified milk-based formula.108 Infants in the fortified group had a

significantly greater height (by 0.9 cm) and growth rate at 12 months, but

this group was also significantly taller at birth. At 12 months, there were

no other statistically significant differences in clinical outcomes, such

as weight, number of acute illnesses, or psychomotor development. Intake

of the iron-fortified formula may have been insufficient to produce a

clinical effect, however; by 8 months of age, 92% of study infants and 85%

of controls were drinking cow's milk rather than study formula. In another

randomized controlled trial in healthy infants from very low income

families, infants randomized to nonfortified formula had significantly

worse psychomotor development (Bayley Scales) at 9 and 12 months o age

compared to those given iron-fortified formula.108a Differences were no

longer significant at 15 months, although sample size may have been

inadequate: only half the sample was assessed at 15 months. There were

no differences at any age in standardized tests of cognitive development

or behavior. These results suggest a clinical benefit from iron-fortified

formula, but further trials are needed to confirm these results and

determine their long-term impact.

Evidence is limited that iron supplementation in healthy pregnant women

with mild or no anemia results in important clinical benefits.109 Clinical

trials have reported that iron supplements in healthy pregnant women

with initial hemoglobins 10 g/dL are efficacious in correcting red cell

indices and iron stores, but they do not improve birth weight, length of

gestation, or other outcome measures when compared to placebo or to no

supplements.110-116 Few of these trials had sufficient statistical power

to detect small positive effects of iron supplementation, however. One

small randomized controlled trial in young pregnant women suggested a

modest beneficial effect of routine iron supplementation on some tests of

psychomotor function, but it had important discrepancies in reported data

and analyses.118 In a large randomized controlled trial of healthy,

nonanemic pregnant women, routine iron therapy was compared to

selective iron therapy given only when a confirmed hemoglobin level

below 10 g/dL was detected after 14 weeks.119 Women in the selective

group had poorer self-reported overall health and increased rates of

transfusion and operative delivery, although differences were small and

may have been due to nonblinding. The routine supplementation group had

more subjective side effects attributable to iron, more postdate

gestations, and higher perinatal mortality; the latter difference was

probably attributable to chance, given small numbers and multiple

comparisons. Evidence thus does not confirm important clinical benefits

from routine iron supplementation in nonanemic pregnant women.

Cohort studies have reported no important adverse effects with iron-

fortified formula,120,121 nor were serious side effects reported in the

clinical trials of iron-fortified food or formula previously cited. Routine

iron supplementation may produce mild, reversible gastrointestinal

symptoms similar to those seen with iron therapy (see above). In one

small, randomized controlled trial, oral iron supplements in iron-

sufficient children resulted in significantly less weight gained after 4

months of treatment,122 but additional studies are needed to confirm

these results. Trials of routine iron supplementation in pregnancy have not

reported adverse effects on pregnancy outcome. The doses of oral iron

typically offered for routine iron supplementation (e.g., in pregnancy) are

unlikely to cause complications of excessive iron storage.98,99 As with

iron therapy, an important hazard of iron prophylaxis is unintentional

overdosage by children in the home; many reported cases of iron ingestion

involve iron-containing prenatal vitamins.100

Recommendations of Other Groups

A number of organizations recommend some form of anemia screening

during infancy and pregnancy. The Institute of Medicine (IOM), the Canadian

Task Force on the Periodic Health Examination, and the Bright Futures

report recommend screening high-risk infants (e.g., preterm or low birth

weight, low socioeconomic status, those fed with cow's milk or

nonfortified formula before 12 months of age) between 6 or 9 and 12

months of age; IOM recommends screening before 3 months in preterm

infants.15,123,124 The American Academy of Pediatrics (AAP) and the

American Academy of Family Physicians (AAFP) recommend that all

infants receive a hemoglobin or hematocrit measurement once during

infancy; the AAP recommends that it be done at or before 9 months of

age.125,126 The recommendations of the AAFP are currently under review.

Prenatal screening for anemia is recommended by the Canadian Task

Force,127 the American College of Obstetricians and Gynecologists

(ACOG),128 and the IOM.15 ACOG recommends measuring a hemoglobin or

hematocrit at the earliest prenatal visit and again early in the third

trimester;128 IOM recommends measuring hemoglobin once in each

trimester.15

Routine screening of older children or nonpregnant adolescents and adults

is not advocated by most organizations.15,124,126,128,129 Some

organizations recommend screening selectively in specific high-risk

populations: adolescents at increased risk due to heavy menses, chronic

weight loss, nutritional deficit, or athletic activity;124 recent

immigrants from undeveloped countries;129 the institutionalized

elderly;129 and nonpregnant women aged 15-25 or otherwise at increased

risk (e.g., with large menstrual blood loss, high parity, poverty, recent

immigration).15 The AAP recommends at least one measurement of

hemoglobin or hematocrit for all menstruating adolescents, preferably at

age 15 years.125 

Primary prevention of iron deficiency anemia in infancy by breastfeeding,

feeding iron-fortified formula if not breastfeeding, and feeding iron-

fortified cereal after 4-6 months of age, is recommended by the Canadian

Task Force,123 IOM,15 AAP,130,131 and Bright Futures.124 The AAFP

recommends counseling parents of children under 6 years of age and

women of childbearing age on the benefits of iron-enriched food and iron

intake.126 The AAP recommends iron supplements in breastfed term

infants who do not receive iron-fortified cereal beginning at 4 months of

age.131 The Canadian Task Force found insufficient evidence to

recommend for or against the routine use of iron supplements in pregnant

women.123 The IOM does not recommend routine iron supplements in

nonanemic pregnant women.15 ACOG and AAP recommend dietary

supplements including iron during pregnancy if dietary intake is

inadequate to meet need, or if there are other risk factors for iron

deficiency.128

Discussion

The burden of suffering from iron deficiency anemia in the general child,

adolescent, and adult populations in the U.S. is low. Although it is

prevalent in certain high-risk groups, mild iron deficiency anemia in the

absence of symptoms appears to have only subtle health consequences in

these individuals. Trials of iron therapy in school children, adolescents,

and adults have not proven important clinical benefits in well-nourished

populations in developed countries. Thus, there is little evidence to

suggest that early detection of iron deficiency anemia in these groups is

beneficial. Treatment of some forms of anemia not caused by iron

deficiency (e.g., vitamin B12 or folate deficiency), and some medical

disorders that cause anemia, which would also be detected if hemoglobin

measurement was performed routinely, can produce dramatic results.

These disorders are too rare in most subgroups of the population to

justify mass screening, however. There is therefore little basis for large-

scale efforts to screen for anemia in the general population.

There is fair evidence to support screening for anemia in pregnant women,

based on numerous observational studies reporting an association between

severe to moderate anemia (hemoglobin <9-10 g/dL) and poor pregnancy

outcome, and weak evidence from a nonrandomized controlled trial and a

cohort study that iron treatment of anemic women improves obstetric

outcomes. Women of low socioeconomic status and immigrants from

developing countries, among whom iron deficiency anemia is more

common, are most likely to benefit from such screening. Because

hemoglobin measurement is a nonspecific test for iron deficiency, further

evaluation should be performed to identify the etiology of anemia detected

by screening. Serum ferritin appears to have the best sensitivity and

specificity for diagnosing iron deficiency in anemic patients. Although

routine iron supplementation improves hematologic indices and iron

status, there is at present insufficient evidence from published clinical

research to suggest that routine iron supplementation of healthy pregnant

women with hemoglobins 10 g/dL is beneficial in improving clinical

outcomes for the mother, fetus, or newborn.109

The prevalence of iron deficiency anemia in the general infant population

is low, and when it occurs in low-risk populations, it tends to be mild. In

healthy, low-risk populations, there are few observational data showing

adverse effects of iron deficiency anemia, nor have there been trials of

early detection and correction of iron deficiency anemia. There is

therefore little evidence to support routine hemoglobin measurement in

infancy for the detection of iron deficiency anemia. On the other hand,

multiple observational studies in high-risk populations (i.e., low

socioeconomic status or developing countries) have found an association

between iron deficiency anemia in childhood and abnormal growth and

development. The largest and most recent trial70 of iron therapy in a

high-risk population showed an important effect of iron therapy on

development, while several trials in high-risk, often malnourished,

infants and children have found beneficial effects of iron on growth and

growth rates. In the U.S., certain infants (e.g., recent immigrants from

developing countries, those of low socioeconomic status, members of

certain minority and ethnic groups, preterm infants, those who begin

cow's milk before 12 months) have a substantially higher prevalence of

iron deficiency anemia and may also be more likely to suffer from general

malnutrition. There is therefore fair evidence to support screening high-

risk infants and toddlers for iron deficiency anemia, using hemoglobin (or

hematocrit). As for pregnant women, evaluation to determine the etiology

of anemia is appropriate. Both breastfeeding and eating iron-fortified

formula and cereal are effective in the primary prevention of iron

deficiency anemia. Given the absence of known adverse effects from such

dietary interventions, and the other important benefits of breastfeeding

(see Chapter 56), evidence supports encouraging mothers to breastfeed

and to include iron-enriched foods in the diet of infants and young

children.

CLINICAL INTERVENTION

A hemoglobin analysis or hematocrit is recommended for pregnant women

at their first prenatal visit ("B" recommendation). There is insufficient

evidence to recommend for or against repeated prenatal testing for

anemia in asymptomatic pregnant women lacking evidence of medical or

obstetrical complications ("C" recommendation). Screening for anemia

with hemoglobin or hematocrit in high-risk infants, preferably at 6-12

months of age, is also recommended ("B" recommendation). Examples of

high-risk infants include infants living in poverty, blacks, Native

Americans and Alaska Natives, immigrants from developing countries,

preterm and low birth weight infants, and infants whose principal dietary

intake is unfortified cow's milk. Although capillary blood specimens are

easier to obtain in infants, a venous blood count provides more accurate

and reliable data. Serum ferritin testing may be useful as an additional

screening test in selected high-risk infants. There is currently

insufficient evidence to recommend for or against periodic screening for

high-risk infants not found to be anemic at initial screening ("C"

recommendation). There is also insufficient evidence to recommend for or

against routine testing for anemia in other asymptomatic persons, but

recommendations against such screening may be made on the grounds of

low prevalence, cost, and potential adverse effects of iron therapy ("C"

recommendation).

Guidelines for normal hemoglobin ranges for infants and pregnant women

have been published.1-4 Appropriate hematological studies and nutrition

counseling should be provided for patients found to have anemia. Compared

to other diagnostic tests, serum ferritin has the best sensitivity and

specificity for detecting iron deficiency in patients found to be anemic.

Screening for hemoglobinopathies is discussed in Chapter 43.

Encouraging mothers to breastfeed their infants and advising parents to

include iron-enriched foods in the diet of infants and young children is

recommended for the primary prevention of iron deficiency anemia ("B"

recommendation). There is also good evidence to recommend breastfeeding

based on proven benefits unrelated to iron deficiency (see Chapter 56).

Pregnant women should receive specific nutritional guidance to enhance

fetal and maternal health (see Chapter 56). There is currently insufficient

evidence to recommend for or against the routine use of iron supplements

for healthy infants or pregnant women who are not anemic ("C"

recommendation).

See the relevant background paper: U.S. Preventive Services Task Force.

Routine iron supplementation during pregnancy. JAMA 1993;270:2846-

2854.

The draft update of this chapter was prepared for the U.S. Preventive

Services Task Force by Carolyn DiGuiseppi, MD, MPH, and was based in part

on a previously published background paper by the U.S. Preventive Services

Task Force (review article by Steven H. Woolf, MD, MPH) and on materials

prepared for the Canadian Task Force on the Periodic Health Examination

by John W. Feightner, MD, MSc, FCFP.

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