Side effects of magnesium sulfate injection for pregnant women include nausea, vomiting, constipation and other symptoms, a few patients may develop pulmonary edema, nystagmus and other symptoms, and respiratory depression may occur in severe cases. Injectable magnesium sulfate can be used as an anticonvulsant, because magnesium ions can inhibit the activity of the central nervous system, and at the same time, magnesium ions also have the effect of diastolic vascular smooth muscle, so it is commonly used in pregnancy hypertension such as pre-eclampsia or eclampsia, and can also be used to treat preterm labor. It should be used with caution in patients with renal insufficiency and the presence of myocardial damage, and is contraindicated in lactating women. Pregnant women should use magnesium sulfate under the guidance of a doctor if appropriate symptoms occur, avoid self-medication, if side effects of magnesium sulfate occur, should contact the relevant doctor for symptomatic treatment.