O31. Magnesium homeostasis and gestational hypertension

Introduction Magnesium (Mg) is important for the normal functioning of muscles and blood vessels. A deficiency has been related to an increase in blood pressure and acute death in heart infarction and stroke. Objectives To review the literature regarding a relation between magnesium homeostasis and gestational hypertension (GH) during pregnancy. Methods A survey of published studies on the subject. Results Mg homeostasis is determined by intake through food and drinking water. A diet rich in proteins and poor in vegetables will increase the excretion of acids in the urine, resulting in a decrease of the normal reabsorption of Mg in the kidneys. Several population studies show that pregnant women often have a Mg intake below the recommended nutritional values. Pregnant women have also been found to have a higher expression of a gene regulating the uptake of Mg from the intestine, suggesting an increased demand for Mg during pregnancy. The incidence of pre-eclampsia (PE) is higher in developing countries, where the risk of nutritional insufficiencies including Mg is high. On the cellular level, results from studies of erythrocyte membranes, brain cells and cerebrospinal fluid suggest that women with PE have lower Mg values than women with normal pregnancies. Several studies show that Mg deficiency during pregnancy is been linked to high blood pressure and PE. Regarding intervention, Mg sulphate intravenously has long been used in the treatment of PE. Data from investigations in four different countries show that supplementation with Mg during pregnancy decreased the risk of GH. The expression of Mg responsive genes has been related to diastolic blood pressure and duration of delivery. Available data thus indicate that GH and PE are related to a lack of Mg. Conclusion From a public health point of view, further studies on Mg homeostasis in pregnancy and intervention in terms of supplementation have a high priority, with the ultimate aim to develop prevention programs.