Optimizing Vitamin D status during pregnancy it thought to have maternal, fetal, and neonatal benefit. Studies suggest that Vitamin D acts well beyond its most commonly thought of role in establishing calcium homeostasis and maintaining maternal and neonatal skeletal integrity. Vitamin D has also been found to modulate the maternal renal renin-angiotensin system, maternal immune response, placental implantation and function, and angiogenesis. In light of this, it is no surprise that the 2010 systematic review of vitamin D in pregnancy suggested that Vitamin D deficiency may be associated with an increase risk in maternal and neonatal morbidity. For example, vitamin D deficiency has correlated with an array of maternal conditions, including gestational hypertension, preeclampsia, gestational diabetes, myopathy, vaginal infection, and mental disease. Associated neonatal risks include preterm birth, immunosuppression, infection, low birth weight, hypokalemia, neonatal seizures, asthma, fractures and rickets.