Non-Anemic Iron Deficiency in Pregnancy: A Cross-Sectional Study of Prevalence and Predictors.

Iron deficiency (ID) is the most common micronutrient deficiency worldwide and the leading cause of anemia in pregnancy. However, non-anemic iron deficiency (NAID) often precedes anemia and is associated with adverse maternal and neonatal outcomes. This cross-sectional study screened pregnant individuals at their first obstetric visit for iron deficiency using both laboratory measures and a standardized risk factor questionnaire. Among 201 participants, 175 completed laboratory testing. The prevalence of ID was 59% (54% NAID 54%, 5% iron deficiency anemia [IDA]), highlighting a substantial burden of iron deficiency early in pregnancy. Key clinical features associated with iron deficiency included higher body mass index (BMI), pagophagia, and prior use of over-the-counter iron supplements. However, a predictive model incorporating these factors demonstrated only modest discrimination (AUC 0.68), indicating that self-reported risk factors alone are insufficient for reliable identification of iron deficiency. These findings suggest that universal laboratory screening, rather than selective testing based on clinical risk profiles, is necessary to detect iron deficiency early in pregnancy. The study underscores the limitations of current United States guidelines, which do not recommend routine iron studies in the absence of anemia, and supports consideration of serum ferritin measurement at the first prenatal visit. Further studies are needed to determine whether early identification and treatment of iron deficiency improves maternal and neonatal outcomes.