ASSOCIATION OF INTRAPARTUM INTAKE OF MAGNESIUM SULFATE AND POSTPARTUM HEMORRHAGE: SYSTEMIC REVIEW
Abstract
Hypertensive disorders of pregnancy such as gestational hypertension, chronic hypertension, and preeclampsia are very challenging because their pharmacological management directly affects the mother and fetus. Preeclampsia is one of the most common complications of pregnancy, which occur during the third trimester and present as new-onset hypertension and proteinuria and further progresses to serious complications such as fatality in both mother and fetus. The cause of preeclampsia is debatable, but intake of Magnesium sulfate during pregnancy is often associated with postpartum hemorrhage.[1]
Magnesium sulfate (MgSO4) is one of the most commonly used medications during labor and in delivery units. The main function of magnesium sulfate is to protect against eclampsia as well as it acts as a neuroprotective agent for fetuses who are at risk of preterm birth.[2]
The mechanism of action of magnesium sulfate is not clearly understood. One of the other side effects of magnesium sulfate is uterine relaxation. This action is mediated by competition with calcium and inhibiting myosin light-chain kinase activity. This theoretical uterine relaxation is not known to stop preterm labor, and therefore it is used as a tocolytic agent and is not recommended usually. Postpartum hemorrhage (PPH) is another major concern that prevents usage of magnesium sulfate and also prevents the uterus contraction appropriately post- delivery.[4]
The previous literature and various studies on the relationship between increased risk of intake of magnesium sulfate and postpartum bleeding are conflicting, with some data suggesting an increased risk of bleeding while other data are providing contradicting data, which reveals no
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significant difference in blood loss at delivery. Postpartum hemorrhage remains a leading cause of maternal morbidity and mortality; therefore, understanding various risk factors for bleeding is essential to prevent any adverse maternal outcomes.[4]
