A lot of research has recently been done in the field of dietary supplements. Ordinary prenatal vitamin supplements show little effect in women with moderately good diets, and it’s difficult to tell if they show any effect in women with poor diets. However, some specific supplements show promise to improve outcomes even in developed nations. Since regions of the world experience vitamin/mineral deficits which are specific to that region, these places may benefit from specific supplements. For instance, there may be a widespread need for a supplement of vitamin A or iodine in the Himalayan regions of upland China, but this doesn’t apply to people in the US, and so the effectiveness of supplements vary by region. This article will look specifically at the effectiveness of calcium and vitamin C supplements on preterm birth and preeclampsia.