Vitamin D testing in pregnancy: does one size fit all?

BACKGROUND: Vitamin D deficiency is common. What the optimum level of vitamin D in pregnancy and whether vitamin D supplementation in pregnancy confers improved health benefits remain controversial. AIM: To assess vitamin D status in pregnant women in a maternity service that recommends routine antenatal screening and advises supplementation where necessary, and to assess relationships between early pregnancy vitamin D levels and changes in vitamin D across pregnancy with pregnancy outcomes. MATERIALS AND METHODS: Vitamin D serum concentrations were measured in early and late pregnancy. The relationships between initial vitamin D status, maternal factors and pregnancy outcomes were estimated. Change in vitamin D over pregnancy was quantified. The relationship between change in vitamin D over pregnancy and pregnancy outcomes was also estimated. RESULTS: Of 1550 women, 849 (55 ) were vitamin D deficient (