Estado de la nutrición de folato, vitamina B12 y hierro en adolescentes embarazadas

Pregnancy in adolescence increases nutritional risk, due to higher demand of nutrients for maternal and fetal growth. This study was aimed to evaluate folate, vitamin B12 and iron status of pregnant adolescents at first trimester of pregnancy. A cross sectional, descriptive study was performed in 122 pregnant adolescents from Valencia, Carabobo state, 1997. Serum and erythrocyte folate and serum vitamin B12 was determined by radioassay; serum ferritin by enzimoimmunoassay; hemoglobin were performed by semi-automated method. Statistical analysis included standard deviation and frequencies. For serum folate 1.7 per cent was found in negative balance and 19.0 per cent at marginal status. For erythrocyte folate, 5.8 per cent was deficient and 1.7 per cent marginal. For serum vitamin B12, 8.3 per cent was deficient and 13.2 per cent marginal. Iron deficiency was found in 19.0 per cent of the adolescents. Prevalence of anemia was of 13.1 per cent, being iron deficiency the main cause. There was high nutritional risk regarding iron status, although iron intakes exceeded the recommendations, but only a small proportion was bioavailable. Prevalence of anemia was lower than reported by other studies and iron deficiency was higher than folic acid and vitamin B12 deficiencies. Pregnant adolescents are at a high biological and nutritional risk.