A study by the University of Southampton has shown that pregnant women respond differently to vitamin D supplements. It was found that the supplement was less effective at increasing the levels of vitamin D in pregnant women if they had their babies in the winter, have low levels of vitamin early in pregnancy or gain more weight. The scientists suggested that the levels of vitamin D given should be tailored according to an individual’s risk factors. Vitamin D deficiency during pregnancy could harm foetal development and the child’s long-term skeletal health. Professor Nicholas Harvey, of the Medical Research Council Lifecourse Epidemiology Unit, University of Southampton, said: “It is important for pregnant women to have sufficient levels of vitamin D for the health of their baby. Our study findings suggest that in order to optimise vitamin D concentrations through pregnancy, the supplemental dose given may need to be tailored to a woman’s individual circumstances, such as the anticipated season of delivery.” The study was published in the Endocrine Society’s Journal of Clinical Endocrinology and Metabolism. Also reported in the Daily Mail and the i newspaper.