What Are the Benefits of Magnesium During Pregnancy?

You may have heard about some of the benefits of magnesium for your health, but let’s talk specifically about why it's important to get enough magnesium when you’re pregnant.

What is Magnesium?

Magnesium is a mineral that is found in many foods such as leafy greens, vegetables, legumes, nuts, seeds, and whole grains. Basically, if the food is a good source of dietary fiber, it’s also a good source of magnesium. Your body needs magnesium because it is a co-factor, or a helper molecule, for over 600 biochemical reactions in the body.

Magnesium enables your body to make energy, form protein, and move your muscles. It also helps regulate your nervous system, is necessary for brain function, and helps your body absorb and use vitamin C and vitamin D. Clearly, your body needs magnesium every day!

Magnesium Benefits

Boosting your magnesium intake during pregnancy has several important benefits for you and baby.

Reduced Risk of Complications

Those who take magnesium throughout their pregnancy are at reduced risk of developing pregnancy complications. These include high blood pressure, preeclampsia or eclampsia, uterine irritability, premature labor or preterm birth, and having a baby with low birth weight or fetal growth restriction.

One randomized controlled trial explored this connection and showed that low serum magnesium levels placed the pregnant woman at an increased risk of having preterm labor or a preterm birth.

Helpful hint: women who start taking a magnesium supplement (typically 400 mg of magnesium) before pregnancy can experience fewer side effects like morning sickness and nausea in the first trimester.

Less Pregnancy Discomfort

Taking magnesium can also help reduce or prevent some of the most common pregnancy complaints. Headaches, night time leg cramps, insomnia and constipation can all be relieved by adding more magnesium to your daily intake.

It can also help with the emotional roller coaster that can accompany pregnancy and the postpartum period. In one clinical trial, researchers looked at the effect of magnesium supplementation on depression. They found that supplementing 248 mg of magnesium daily led to a significant difference in the incidence of depression and anxiety symptoms in their participants when compared to those who received a placebo. While this study was completed on non-pregnant individuals, it is reasonable to think that magnesium supplementation would have the same effect both during pregnancy and the immediate postpartum.

Magnesium is safe to take while you’re pregnant and breastfeeding, so it’s completely fine to continue your supplementation even after baby is born.

How Do I Know if I’m Getting Enough Magnesium?

There a blood test available to check your magnesium levels—it lets you know the serum magnesium levels in your body. But magnesium is mostly stored in the bones and soft tissues of your body, so this blood test doesn’t give the most accurate picture of your body’s magnesium reserve. Because of that, the best way to know if your body needs more magnesium may be to pay attention to what your body is telling you.

What Are the Symptoms of Magnesium Deficiency?

There are several signs and symptoms that could indicate you’re not getting enough magnesium. Some of these signs include:

  • Nausea and vomiting
  • Loss of appetite
  • Headaches or migraines
  • Abnormal heart rhythms
  • Sleepiness/fatigue
  • Muscle cramps or contractions
  • Depression or anxiety

What Form of Magnesium Should I Take?

There are many kinds of magnesium to choose from: citrate, malate, oxide, glycinate are just a few of the options! The kinds that dissolve in water tend to be more bioavailable and certain types are better for various symptoms. For example, magnesium glycinate helps with headaches. Magnesium citrate and magnesium malate are both helpful to reduce issues with constipation. Magnesium oxide is a great all-around choice for oral magnesium supplementation, as it helps with all of the symptoms of magnesium deficiency and also contains more magnesium in each dose than the other forms.

If you take a magnesium supplement, please note that zinc can interfere with the body’s ability to absorb magnesium so any zinc supplements should be taken separately.

If you have questions about adding an oral magnesium supplement to your diet, talk to your healthcare provider about your options to see which supplement would be the best one for you and your baby.

About the Author

Rebekah Mustaleski is a Medical Advisor for Motif Medical. She is a Certified Professional Midwife with Roots & Wings Midwifery, where she promotes evidence-based maternity care for families seeking an out-of-hospital delivery.

Information provided in blogs should not be used as a substitute for medical care or consultation.


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