Can you take magnesium citrate while pregnant?

Can you take magnesium citrate while pregnant?

Yes, magnesium citrate can be taken during pregnancy, but context matters. As a dietary supplement at standard doses, it's generally considered safe. As a laxative at higher doses, it should only be used under medical guidance.

Magnesium plays a role in over 300 enzymatic reactions in the body. During pregnancy, your need for it increases to support fetal bone development, muscle function, and nerve signaling. The recommended dietary allowance for magnesium during pregnancy is 350-360 mg per day, depending on your age.

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Understanding the two uses of magnesium citrate

This is where confusion often crops up. Magnesium citrate serves two very different purposes depending on the dose.

As a dietary supplement, magnesium citrate provides elemental magnesium at doses typically ranging from 200-400 mg daily. At these levels, it's well tolerated and supports muscle relaxation, blood pressure regulation, and nerve function.

As a laxative, magnesium citrate is sold in liquid form (often in bottles at the pharmacy) and works by pulling water into the intestines. The dose is much higher, and it can cause diarrhea, cramping, and electrolyte shifts. During pregnancy, dehydration and electrolyte imbalances carry real risks, which is why laxative-dose magnesium citrate requires medical supervision.

What does the research say?

A Cochrane systematic review on magnesium supplementation in pregnancy evaluated multiple randomized controlled trials and found that magnesium supplementation may be associated with a lower risk of fetal growth restriction and preterm birth, though the authors noted that the quality of evidence was mixed and more research is needed.

A 2022 meta-analysis in Food Science & Nutrition examining magnesium supplementation in gestational diabetes patients found that magnesium improved fasting plasma glucose and insulin resistance markers.

Which form of magnesium is best during pregnancy?

The form matters. Magnesium glycinate is often the preferred choice for pregnancy because of its high bioavailability (estimated around 80%) and minimal GI side effects. Magnesium oxide, while common, is poorly absorbed (as low as 4% bioavailability) and more likely to cause stomach issues. Magnesium citrate falls in between and can have a mild laxative effect, which some pregnant people find helpful for constipation.

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A note from WeNatal on magnesium during pregnancy

WeNatal Rest + Digest Magnesium combines a blend of magnesium glycinate, magnesium malate, magnesium citrate, and magnesium gluconate to support absorption, relaxation, and digestive comfort during pregnancy. Paired with WeNatal for Her, it helps round out your prenatal nutrition. As always, check with your provider before adding any new supplement to your routine.

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References

Fanni D, et al. (2021). The role of magnesium in pregnancy and in fetal programming of adult diseases. Biological Trace Element Research, 199:3647-3657. DOI: 10.1007/s12011-020-02513-0

Makrides M, et al. (2014). Magnesium supplementation in pregnancy. Cochrane Database of Systematic Reviews, 4:CD000937. DOI: 10.1002/14651858.CD000937.pub2

Qu X, et al. (2022). Effect of magnesium supplementation on pregnancy outcome in gestational diabetes mellitus patients: A meta-analysis. Food Science & Nutrition, 10(10):3193-3202. DOI: 10.1002/fsn3.2561