Vitamin D deficiency and insufficiency is common during pregnancy.

The objective was to determine the incidence of vitamin D deficiency, insufficiency, and sufficiency in African-American, Hispanic, and Caucasian pregnant women. Blood samples were taken from 154 African-American, 194 Hispanic, and 146 Caucasian women at <14 weeks of gestation; 25 hydroxyvitamin D levels (25(OH)D) levels were measured by radioimmunoassay. The mean 25(OH)D levels in African-American, Hispanic, and Caucasian pregnant women were 15.5 ± 7.2 (standard deviation), 24.1 ± 8.7, 29.0 ± 8.5 ng/mL, respectively. Ninety-seven percent of African-Americans, 81% of Hispanics, and 67% of Caucasians were deficient (25(OH)D levels <20 ng/mL or <50 nmol/L) or insufficient (25(OH)D levels ≥ 20 ng/mL or <32 ng/mL or ≥ 50 nmol/L or <80 nmol/L). Of these pregnant women, 82% had vitamin D levels <32 ng/mL (<80 ng/mL). In logistic regression models, race was the most important risk factor for vitamin D deficiency or insufficiency. African-American women and Hispanic women were more likely to have vitamin D insufficiency and deficiency than Caucasian women. Furthermore, primigravid women were more at risk for vitamin D insufficiency. This study demonstrates widespread vitamin D deficiency and insufficiency in pregnant females living at a southern latitude. African-Americans are at greatest risk.