Global prevalences of erythropoiesis-associated micronutrient deficiencies (iron, folate, and vitamin B12) among pregnant women: a systematic review and meta-analysis

Deficiencies of iron, folate, and vitamin B12 micronutrients are considered a global public health issue. These deficiencies not only lead to anemia but are also linked to numerous short- and long-term health risks for both mothers and children. This study aimed to estimate the global prevalence of erythropoiesis-associated micronutrient deficiencies (iron, folate, and vitamin B12) in pregnant women. We systematically searched three databases, including PubMed, Embase, and Scopus, along with a manual search for observational studies published up to August 26, 2024. Data extraction was independently screened by two reviewers. Random-effects models were employed to pool data on prevalences of iron, folate, and vitamin B12 deficiencies among pregnant women. We identified 43 studies from 28 countries. Global pooled prevalences of single iron, folate, and vitamin B12 deficiencies were 28.4% (95% CI, 21.1–37%), 11.1% (95% CI, 3.9–27.5%), and 17.1% (95% CI, 8.8–30.6%), respectively. Pooled prevalences of double micronutrient deficiencies of iron or folate were 53.1% (95% CI, 49.8–56.5%) and 49.6% (95% CI, 46.2–53%), respectively; double micronutrient deficiencies of folate or vitamin B12 were 6.2% (95% CI, 1.2–25.8%) and 11.8% (95% CI, 3.3–34.1%), respectively. Pooled prevalences of triple micronutrient deficiencies of iron or folate or vitamin B12 were 36.1% (95% CI, 13.1–68%), 34.3% (95% CI, 16.9–57.3%), and 12.6% (95% CI, 7–74.8%), respectively. The findings highlight the high prevalences of erythropoiesis-related micronutrient deficiencies in pregnant women worldwide. Targeted interventions to mitigate these deficiencies during pregnancy.