Vitamin D status is inversely associated with anemia and serum erythropoietin during pregnancy

• Published in: The American journal of clinical nutrition 2015-11, Vol.102 (5), p.1088-1095
• Main Authors: Thomas, Carrie E, Guillet, Ronnie, Queenan, Ruth A, Cooper, Elizabeth M, Kent, Tera R, Pressman, Eva K, Vermeylen, Francoise M, Roberson, Mark S, O'Brien, Kimberly O
• Format: Article
• Language: English
• Subjects: 25-Hydroxyvitamin D 2 - blood; Adolescent; Anemia, Iron-Deficiency - complications; Anemia, Iron-Deficiency - epidemiology; Biomarkers - blood; Calcifediol - blood; Cohort Studies; Cross-Sectional Studies; Erythropoietin - blood; Female; Hemoglobin; Hemoglobins - analysis; Humans; Linear Models; Longitudinal Studies; Maternal Nutritional Physiological Phenomena; New York - epidemiology; Nutritional Status; Pregnancy; Pregnancy Complications - blood; Pregnancy Complications - epidemiology; Prospective Studies; Regression analysis; Risk; Risk assessment; Teenagers; Vitamin D; Vitamin D Deficiency - blood; Vitamin D Deficiency - complications; Vitamin D Deficiency - epidemiology; Vitamin deficiency
• ISSN: 0002-9165; 1938-3207
• DOI: 10.3945/ajcn.115.116756

Vitamin D and iron deficiencies frequently co-exist. It is now appreciated that mechanistic interactions between iron and vitamin D metabolism may underlie these associations. We examined interrelations between iron and vitamin D status and their regulatory hormones in pregnant adolescents, who are a group at risk of both suboptimal vitamin D and suboptimal iron status. The trial was a prospective longitudinal study of 158 pregnant adolescents (aged ≤18 y). Maternal circulating biomarkers of vitamin D and iron were determined at midgestation (∼25 wk) and delivery (∼40 wk). Linear regression was used to assess associations between vitamin D and iron status indicators. Bivariate and multivariate logistic regressions were used to generate the OR of anemia as a function of vitamin D status. A mediation analysis was performed to examine direct and indirect relations between vitamin D status, hemoglobin, and erythropoietin in maternal serum. Maternal 25-hydroxyvitamin D [25(OH)D] was positively associated with maternal hemoglobin at both midgestation and at delivery (P < 0.01 for both). After adjustment for age at enrollment and race, the odds of anemia at delivery was 8 times greater in adolescents with delivery 25(OH)D concentrations