Magnesium salts in pregnancy

Abstract

Magnesium is one of the most abundant elements in the body. Although the total serum magnesium content does not represent more than 1% of total body magnesium, serum magnesium determinations have been routinely used in clinical practice to assess body magnesium status. Thus, serum magnesium concentration ranges from 1.8 to 2.2 mg.dl−1 (0.75–0.95 mmol.l − 1 or 1.5–1.9 mEq.l − 1). Consequently, when serum magnesium levels fall below the range considered normal, the patient is diagnosed with hypomagnesemia. This deficiency has been associated with low-grade systemic inflammation, increased levels of proinflammatory molecules, mitochondrial dysfunction, increased reactive oxygen species production, and hypertriglyceridemia leading to an increase in the number of easily oxidizable lipoproteins in the circulation. Several magnesium salts have been used to treat hypomagnesemia during pregnancy, with magnesium sulfate (MgSO4) being the most commonly used magnesium salt in current obstetric practice. However, the exact mechanism of action of MgSO4 remains largely an enigma, and its parenteral use poses a significant toxicological risk at high doses. In this review, we summarize the use of magnesium salts during pregnancy not only from a clinical point of view but also, with the use of computational simulations, discuss advances in the understanding of the molecular mechanisms of action of magnesium salts, with emphasis on MgSO4. These molecular simulations are required to unveil the pharmacological action of the magnesium salts during pregnancy. MgSO4 plays a role as an antioxidant agent at the plasma membrane level which can explain the mechanism of action of this salt in current obstetric practice.