High folate and low vitamin B12 status during pregnancy is associated with gestational diabetes mellitus Abstract Background & Aims—B-vitamins and homocysteine may contribute to the development of gestational diabetes mellitus (GDM), but existing studies are inconsistent. We examined the crosssectional associations of plasma folate, vitamins B6, B12, and homocysteine concentrations with GDM and glycaemia in a sample of...