Vitamin B12 deficiency in newly-arrived pregnant refugees in Calgary, Canada from 2015-2020

ABSTRACT Background Vitamin B12 deficiency is linked to adverse maternal and infant outcomes, such as preterm birth and low birth weight. Pregnant refugees are particularly vulnerable to nutritional deficiencies due to food insecurity and gastrointestinal conditions. However, limited research has explored the prevalence of B12 deficiency among pregnant refugees in Canada. Objective To determine the prevalence of vitamin B12 deficiency in pregnant refugees receiving care at the Mosaic Refugee Health Clinic (MRHC) in Calgary and to examine their demographic and clinical characteristics. Methods We conducted a retrospective chart review for pregnant patients at MRHC with estimated delivery dates between November 2015 to December 2020. We assessed the association between B12 deficiency and demographic characteristics, anemia, iron deficiency, macrocytosis, and relevant infectious diseases using chi-square tests and Fisher’s exact tests. Results Of 159 pregnant refugee patients tested for B12, 42.8% (n=68) had B12 deficiency (<220 pmol/L), 50.3% (n=80) had iron deficiency (ferritin <30 ul/L), 54.7% (n=87) were anemic (hemoglobin <110 g/L), and <5 had macrocytosis. Among patients with B12 deficiency, 58.8% (n=40) had concomitant iron deficiency. B12 deficiency was significantly associated with later gestational age at first prenatal visit (p=0.034). There was an association between B12 status and hemoglobinopathy (p=0.027), but it was not in the expected direction. No significant associations were found with other demographic or clinical characteristics (p> 0.050). Conclusion B12 and iron deficiency were common among newly arrived pregnant refugees, suggesting poor nutritional status. The absence of macrocytosis was insufficient to rule out B12 deficiency. Screening for B12 deficiency during pregnancy, while not recommended in Canada, may be considered for refugees.