The prevalence and risk factors associated with Iron, vitamin B12 and folate deficiencies in pregnant women: A cross-sectional study in Mbeya, Tanzania

Maternal nutrition is an important forecaster of infant’s and mother’s health status in most developing countries. This study aimed at assessing the prevalence and associated risk factors of iron, vitamin B12, and folate deficiencies among pregnant women in Mbeya Tanzania. A cross-sectional study using a cluster randomized sampling was conducted among 420 pregnant women. A structured questionnaire was used to collect socio-demographic and dietary assessment. Body iron store was assessed using serum ferritin measured by immunoturbidimetric assays using a Roche Cobas 400+ biochemistry analyzer. Serum folate was measured by folate microbiological assay, while serum vitamin B12 was measured by immunochemiluminescence assay using a Roche Cobas e411 immunoassay analyzer. Multivariate analysis was performed using Poisson regression. The prevalence of iron, folate, and vitamin B12 deficiencies among pregnant women in Mbeya was 37.8%, 24.0%, and 9.7% respectively. Higher odds of iron deficiency were seen in pregnant women aged 20–24 years older [Adjusted OR = 1.20 (95%CI 1.03, 1.35)], not employed [Adjusted OR = 3.0(95%CI 1.03–1.77)] and, not received iron/folic acid supplementation [Adjusted OR = 1.11 (95%CI 1.003–1.23)]. Pregnant women with highest and middle socio-economic statuses had lower odds of vitamin B12 deficiency [Adjusted OR = 0.83 (95%CI 0.76–0.92)] and [Adjusted OR = 0.89 (95%CI 0.81–0.98)] respectively. Pregnant women who were not employed, not received iron and folic acid supplement during pregnancy and, not consumed edible vegetable cooking oil had significant higher odds of serum folate deficiency [Adjusted OR = 3.0 (95%CI 1.58–5.68)], [Adjusted OR = 1.53 (95%CI 1.21–1.93)] and, [Adjusted OR = 2.77 (1.03–7.44)] respectively. This study confirms that iron, folate and vitamin B12 deficiencies are still a major challenge among pregnant women in Tanzania. We recommend for public health interventions for the provision of vitamin B12 along with iron and folic acid supplementations, especially in pregnant women belong to low socio-economic status and limited knowledge of healthy diet.