POST-HOC ANALYSIS OF VITAMIN D STATUS AND REDUCED RISK OF PRETERM BIRTH IN TWO VITAMIN D PREGNANCY COHORTS COMPARED WITH SOUTH CAROLINA MARCH OF DIMES 2009-2011 RATES

摘要

BackgroundTwo vitamin D pregnancy supplementation trials were recently undertaken in South Carolina: The NICHD (n=346) and Thrasher Research Fund (TRF, n=163) studies. The findings suggest increased dosages of supplemental vitamin D were associated with improved health outcomes of both mother and newborn, including risk of preterm birth (<37 weeks gestation). How that risk was associated with 25(OH)D serum concentration, a better indicator of vitamin D status than dosage, by race/ethnic group and the potential impact in the community was not previously explored. While a recent IOM report suggested a concentration of 20 ng/mL should be targeted, more recent work suggests optimal conversion of 25(OH)D to 1,25(OH)2D takes place at 40 ng/mL in pregnant women.