Vitamin D Insufficiency Is Prevalent among Pregnant African American Adolescents

Study Objective: Recent attention has focused on vitamin D insufficiency but few data exist on vitamin D status among pregnant minority youth. Design: A screening study was undertaken in adolescents having prenatal blood samples drawn for other routine tests obtained during the second trimester (18 +/- 1.8 week gestation, n = 44) or third trimester of pregnancy (28.4 +/- 2.1 week gestation, n = 36). Serum 25- hydroxyvitamin D (25(OH)D) was measured and significant determinants of vitamin D insufficiency in this cohort were identified. Setting: Urban prenatal clinic. Participants: Eighty pregnant African American adolescents <= 18 y of age). Main Outcome Measure(s): Vitamin D status, STDs, hemoglobin, season, birth weight Results: Serum 25(OH)D in this group averaged 21.6 +/- 8 ng/mL (age 16.5 +/- 1.1 y, n = 80), and did not significantly differ between the second (20.95 +/- 8.2 ng/mL, n = 44) and third trimester cohorts (22.5 +/- 7.9 ng/mL, n = 36). Vitamin D insufficiency (< 20 ng/mL) was evident in 46.25% and vitamin D deficiency (<15 ng/mL) was evident in 21.25% of those studied. Significant predictors of suboptimal vitamin D status included sampling during the winter months (P = 0.004), lower hemoglobin concentration (P = 0.019), and higher second trimester leptin levels (P = 0.018). Inverse associations between 25(OH)D and bacterial vaginosis were evident when controlled for season of sampling (P = 0.02, n = 80). Conclusions: Vitamin D insufficiency was prevalent among urban pregnant minority adolescents. Further studies are needed to address the impact of this finding on maternal and neonatal calcium homeostasis and bone health.