A 42-year-old high risk pregnant female presented with hyponatremia from multiple causes and was treated with total parenteral nutrition. She developed acute hypernatremia due to the stage of pregnancy and other comorbidities. All the mechanisms of hyponatremia and hypernatremia were summarized here in our case report. This case has picture (graph) representation of parameters that led to changes in serum sodium and radiological findings of central pontine myelinolysis on MRI. In conclusion we present a complicated case serum sodium changes during pregnancy and pathophysiological effects on serum sodium changes during pregnancy.