The role of magnesium sulfate in pregnancy

Pregnant women are subject to constant care throughout the pregnancy. For decades, magnesium sulfate has been used in obstetrics for thousands of pre-birth women to prevent premature birth and reduce uterus sysentation.

1. What is magnesium sulfate?

Magnesium sulfate (MgSO4) is an inalized salt of magnesium, in medicine this drug is prepared in 2 forms as follows:

  • White oral administration: Has a laxative and bile effect, so it is often used to treat constipation and inflammation of the gallbladder. In addition, magnesium sulfate is also very effective in cleaning the intestines before carrying out diagnostic procedures or cases of poisoning;
  • Solution for intravenous or intramuscular injection: Used to lower blood pressure and dilate vessels, besides having a diuretic effect, helping to remove the water from the body.

When it comes to magnesium sulfatein obstetrics , this drug is also known for its effectiveness in reducing the force of theuterus , anti-convulsions in blood poisoning, treatment of premature birth and reduction of blood magnesium.

2. The role of magnesium sulfate in pregnancy

The American College of Obstetrics and Gynecology (ACOG) and the Association of Mothers Medicine have long advocated the use of short-term magnesium sulfate (usually less than 48 hours) in the treatment and care of pregnant women based on appropriate conditions and times. Specifically, intravenous infusion of magnesium sulfate is in dinhated when the pregnant woman encounters the following symptoms:

  • Increased uterus toys;
  • Hypertension;
  • Seizures associated with pre-seizures and seizures;
  • Edema;
  • Blood clots;
  • Affected by sedatives;
  • Lack of magnesium blood;
  • Pregnant women are at risk of premature birth before 32 weeks of gestation.


In some cases, the pregnant woman will be prescribed by the doctor to transmit a drip of magnesium sulfate intravenously

In addition to the main role of prevention and treatment of seizures in women with pre-seizures or seizures, medical experts also claim that magnesium sulfate has a protective effect on the fetal nerves when premature birth is predicted (less than 32 weeks of pregnancy). Specifically, magnesium sulfate can reduce a child's risk of cerebral palsy and coarse motor dysfunction by about 30-40%. In particular, magnesium sulfate also helps to extend the gestation period up to 48 hours, so that it is possible to apply Corticoid therapy before birth in pregnant women between 24-34 weeks at risk of premature birth within 7 days.

3. Does magnesium sulfate have side effects?

In general, magnesium salts should only be used for a short period of 3-7 days because if treatment lasts, the drug risks accumulating in the mother's body and causing respiratory failure as well as hypoxia in the fetus. In addition, magnesium sulfate is not recommended during the first 3 months of pregnancy.

Pregnant women should also stop using magnesium sulfate before labor on the reason that magnesium can pull calcium out of bone tissue. Therefore, long-term exposure to magnesium sulfate while still lying in the uterus will make the bones of the fetus and newborn become weaker and more fragile during labor. According to results from some epidemiological analyses, there were 18 cases of long fractures in fetuses and babies when exposed to pre-birth magnesium sulfate for an average of 9.6 weeks, with an average total dose of 3,700 g. However, the long duration and dosage as above both exceed the recommended levels of magnesium sulfate in obstetrics.

In addition, the U.S. Food and Drug Administration (FDA) believes that using magnesium sulfate injections longer than 5-7 days carries a risk of premature birth in pregnant women. For this reason, the safety level of magnesium sulfate in obstetrics has been changed in classification from Group A to Group D and added new warning information on the packaging label.

Care for premature babies at home

Use of magnesium sulfate injections longer than 5-7 days is at risk of leading to premature birth in pregnant women

Meanwhile, a drug used to inhibit early labor called Toccytics is not recommended before week 24 and after week 34 of pregnancy. Moreover, the prolonged use of magnesium sulfate is never in its inerated. Therefore, health experts say it is still advisable to continue using magnesium sulfate because the FDA's re-classification is un proven and sub-standard.

4. Contraint potassium sulfate use contraintation in pregnancy

The contraindications of magnesium sulfate in obstetrics are similar to those in the prevention of obstetrics and seizures, specifically cases in which pregnant women are not allowed to use magnesium sulfate including:

  • Hypersensitivity to the components of the drug;
  • Myalnia cons;
  • Severe liver disease;
  • Fetal malformations;
  • Genetic abnormalities.

In the case of pregnant women with renal failure, it is recommended to reduce the dose and monitor the level of magnesium in the blood.

5. Monitoring of pregnant women when using magnesium sulfate

When using magnesium sulfate in obstetrics, factors that need to be monitored in the mother include:

  • Blood pressure;
  • Heart rate;
  • Breathing;
  • Deep tendons (patella);
  • Reflexes;
  • Excreted.

Although taking magnesium sulfate in obstetrics is a fairly common form of treatment, it is only used on a doctor's request and requires caution. Undesirable effects occur on the mother and baby depending on the dosage and do not comply with the time in which. There is now sufficient evidence in support of the use of magnesium sulfate in obstetrics to help with the functioning of the uterus, limit seizures associated with pregnancy accidents and reduce the risk of cerebral palsy in premature babies.

If you have abnormal symptoms, you should be examined and consulted with a specialist.

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  • Instructions for proper, safe magnesium supplementation
  • Why do you need magnesium supplements for pregnant women?
  • Foods high in Magnesium

About: Minh Quynh

b1ffdb54307529964874ff53a5c5de33?s=90&d=identicon&r=gI am the author of I had been working in Vinmec International General Hospital for over 10 years. I dedicate my passion on every post in this site.


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