Iron-Deficiency Prevalence and Supplementation Practices Among Pregnant Women: A Secondary Data Analysis From a Clinical Trial in Vancouver, Canada

Abstract

Background North American public health guidelines recommend supplementation with an iron-containing prenatal multivitamin throughout pregnancy to meet the Recommended Daily Allowance (RDA) of 27 mg elemental iron daily. However, whether supplementation with standard prenatal multivitamins is sufficient to prevent maternal iron deficiency is unclear, as needs increase substantially with advancing gestation Objective This study aimed to assess iron status in early and late pregnancy among 60 pregnant women receiving 27 mg/day elemental iron as part of a randomized trial in Vancouver, Canada Methods Study visits were conducted at 8-21 (baseline) and 24-38 (endline) weeks’ gestation. Venous blood specimens were collected for a complete blood count and measurement of iron and inflammatory biomarkers. Supplementation with any additional iron (beyond 27 mg/day) was reported by participants (treatment with additional iron is recommended if ferritin <30 µg/L). Quantile regression was used to explore predictors of endline ferritin concentrations, including ethnicity, education, income, and baseline ferritin Results Overall, n = 60 and n = 54 women participated in baseline and endline visits, respectively. Rates of probable iron deficiency (ferritin <30 µg/L) at baseline and endline were: n = 22 (41%) and n = 44 (81%). Less than half (n = 18; 41%) of participants with probable iron deficiency at endline reported supplementation with additional iron. Ethnicity was the only significant modifier of endline ferritin, with higher concentrations in those of South, East, and Southeast Asian ethnicity compared to European (β = 10.4 µg/L, 95% CI = 0.3-20.5) Conclusion Pregnant individuals may require additional supplemental iron beyond 27 mg to meet requirements in later pregnancy, given the high rates of iron deficiency observed in this clinical trial, despite consumption meeting 100% of the RDA Trial registration: ClinicalTrials.gov (identifier: NCT04022135)

Optimizing diagnosis and treatment of iron deficiency and iron deficiency anemia in women and girls of reproductive age: Clinical opinion

“…were never tested at all. Lower-income status was negatively associated with the likelihood of ever testing, corroborating the results of Hamm et al 55 In a provocative prospective study, flying in the face of existing guidelines reporting insufficient evidence to screen for ID at presentation routinely, Cochrane et al 56…”

“…Twenty‐five percent were severe at some time during the pregnancy, and 40% were never tested at all. Lower‐income status was negatively associated with the likelihood of ever testing, corroborating the results of Hamm et al 55 In a provocative prospective study, flying in the face of existing guidelines reporting insufficient evidence to screen for ID at presentation routinely, Cochrane et al 56 screened pregnant women with serum ferritin. To correct for the acute phase reactivity of the serum ferritin, which occurs with inflammation, the authors used BRINDA (Biomarkers Reflecting the Inflammation and Nutritional Determinants of Anemia) 57 .…”

Identification and treatment of iron‐deficiency anemia in pregnancy and postpartum: A systematic review and quality appraisal of guidelines using AGREE II

“…Parenteral iron is a safe and effective way to rapidly replenish iron stores in pregnancy and is noted to be more effective than oral iron preparations in correcting anemia with fewer gastrointestinal side effects. 40 Parenteral iron should be considered in cases where oral iron is ineffective, 21,24,25,28,[34][35][36] the individual is intolerant or experiences malabsorption (e.g., patients with a history of gastric surgery or conditions such as inflammatory bowel disease which can interfere with oral iron absorption), 18,21,[24][25][26]28,32,34,35 the individual is non-compliant, 34,36 or the anemia is severe. 18,25,36 Parenteral iron is not advised during the first trimester 18,19,21,24,[34][35][36] because of a lack of safety data.…”

“…20,28,32,34,35 Most guidelines defined postpartum anemia as hemoglobin less than 100 g/L. 24,25,28,35,36 Alternative definitions included hemoglobin less than 110 g/L, 21 and less than 120 g/L. 20,32,34 Oral iron supplement was recommended in the treatment of stable, asymptomatic (or mildly symptomatic) postpartum patients, at a dose between 40 and 200 mg/day for 3 months.…”

“…20,21,24,28,32,[34][35][36] Similar to antenatal recommendations, postpartum patients with IDA should be monitored with repeat hemoglobin in 2-4 weeks following treatment commencement, with an expected 10-20 g/L increase, respectively. 20,24,36 Parenteral iron was recommended in cases where there is poor adherence to oral iron, 36 if oral iron is not tolerated, or if it is ineffective. 21,24,32,[34][35][36] In contrast, DSOG guidelines provided a conditional recommendation against the use of parenteral iron for the treatment of anemia during the postpartum period.…”