in progress

Draft Research Plan

Iron Deficiency and Iron Deficiency Anemia During Pregnancy: Screening and Supplementation

April 07, 2022

Recommendations made by the USPSTF are independent of the U.S. government. They should not be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.

  1. What are the benefits of routine iron supplementation during pregnancy on maternal and infant health outcomes?
  2. What are the harms of routine iron supplementation during pregnancy?
  3. In pregnant persons with or without anemia, what is the association between change in maternal iron status (including changes in ferritin or hemoglobin level) and improvement in newborn and peripartum outcomes in U.S.-relevant populations?
  1. What are the benefits of screening for iron deficiency anemia in asymptomatic pregnant persons on maternal and infant health outcomes?
  2. What are the harms of screening for iron deficiency anemia in pregnant persons?
  3. What are the benefits of treatment of iron deficiency anemia during pregnancy on maternal and infant health outcomes?
  4. What are the harms of iron treatment in pregnant persons?
  5. In pregnant persons with iron deficiency, with or without anemia, what is the association between change in maternal iron status (including changes in ferritin or hemoglobin level) and improvement in newborn and peripartum outcomes in U.S.-relevant populations?

Contextual questions will not be systematically reviewed and are not shown in the Analytic Framework.

  1. What are the current practices in identifying pregnant persons with iron deficiency anemia? Do current practices of identification differ by race and ethnicity, age, socioeconomic status, cultural factors, educational attainment, or health literacy level?
  2. What are current practices for the use of iron supplementation during pregnancy? Do current practices differ by race and ethnicity, age, socioeconomic status, cultural factors, educational attainment, or health literacy level?
  3. How well do risk assessment tools identify pregnant persons at increased risk for iron deficiency anemia?

The Research Approach identifies the study characteristics and criteria that the Evidence-based Practice Center will use to search for publications and to determine whether identified studies should be included or excluded from the Evidence Report. Criteria are overarching as well as specific to each of the key questions (KQs).

Category Included Excluded
Populations Asymptomatic adolescents (ages 13 to <18 years) and adults (age ≥18 years), regardless of iron status, who are pregnant and their infants Nonpregnant persons; persons with underlying diagnosis or symptoms of anemia; and severely malnourished populations not representative of those in the United States
Interventions Oral iron supplementation and iron-fortified foods Nonoral forms of iron
Comparators All KQs: No supplementation

KQ 3: Change in maternal iron deficiency, iron deficiency anemia status, or both

 
Outcomes KQ 1: Maternal health outcomes: Mortality; health-related quality of life; preeclampsia (severe); postpartum hemorrhage; blood transfusion; and postpartum depression
Maternal intermediate outcomes: Incidence of iron deficiency anemia; incidence of iron deficiency; hematologic indices and ferritin levels; and Caesarean delivery rates
Infant health outcomes: Perinatal mortality, respiratory distress, and neonatal intensive care unit admission
Infant intermediate outcomes: Hematologic indices and ferritin levels; low birth weight, small for gestational age size, and preterm delivery

KQ 2: More serious harms; harms leading to discontinuation; and accidental overdose

 
Settings U.S. primary care–relevant settings  
Timing KQ 1: Long-term outcomes

KQ 2: Short- or long-term outcomes

 
Study designs KQ 1: Randomized, controlled trials; controlled cohort studies; and other controlled observational studies

KQ 2: Studies from KQ 1 and large uncontrolled observational studies

KQ 1: Uncontrolled studies

Abbreviation: KQ=key question.

Category Included Excluded
Populations KQs 1 and 2: Pregnant adolescents and adults asymptomatic for iron deficiency anemia and their infants

KQs 3 and 4: Pregnant adolescents and adults with iron deficiency anemia and their infants

KQ 5: Pregnant persons with iron deficiency, with or without anemia, and their infants
Severely malnourished populations not representative of those in the United States; persons symptomatic for iron deficiency anemia
Interventions

KQs 1 and 2: Screening for iron deficiency anemia

KQs 3 and 4: Oral or intravenous iron supplementation and iron-fortified foods

Nonoral and nonintravenous forms of iron
Comparators KQs 1 and 2: No screening for iron deficiency anemia

KQs 3 and 4: No treatment

KQ 5: A change in maternal iron deficiency, iron deficiency anemia status, or both
 
Outcomes KQs 1, 3, 5: Maternal health outcomes: Mortality; health-related quality of life; preeclampsia (severe); postpartum hemorrhage; blood transfusion; and postpartum depression
Maternal intermediate outcomes: Caesarean delivery rates; incidence of iron deficiency anemia; incidence of iron deficiency; hematologic indices and ferritin levels
Infant health outcomes: Perinatal mortality, morbidity (neonatal intensive care unit admission, respiratory distress)
Infant intermediate outcomes: Hematologic indices and ferritin levels; low birth weight, small for gestational age size, and preterm delivery

KQ 2: Overdiagnosis, anxiety, and labeling

KQ 4: More serious harms; harms leading to discontinuations; and overtreatment

 
Settings U.S. primary care–relevant  
Timing KQs 1 and 3: Long-term outcomes

KQs 2 and 4: Short- or long-term outcomes

 
Study designs KQs 1 and 3: Randomized, controlled trials; controlled cohort studies; and other controlled observational studies

KQs 2 and 4: Studies included from other KQs and large uncontrolled observational studies

KQ 5: Association studies

KQ 1 and 3: Uncontrolled studies

Abbreviation: KQ=key question.