What does fact checked mean?
At Healthfully, we strive to deliver objective content that is accurate and up-to-date. Our team periodically reviews articles in order to ensure content quality. The sources cited below consist of evidence from peer-reviewed journals, prominent medical organizations, academic associations, and government data.
The information contained on this site is for informational purposes only, and should not be used as a substitute for the advice of a professional health care provider. Please check with the appropriate physician regarding health questions and concerns. Although we strive to deliver accurate and up-to-date information, no guarantee to that effect is made.
Side Effects of Magnesium in Pregnancy
Each day, healthy women need between 310 and 320 milligrams of magnesium, a mineral that every organ in the body needs to function properly. During pregnancy, a woman's nutritional needs change to account for the added stress a growing fetus puts on her body. For this reason, pregnant women need to increase their daily intake of magnesium to between 350 and 360 milligrams. Magnesium-rich foods, including almonds, soybeans, spinach and oatmeal, are the best sources of this mineral for pregnant women. Pregnant women who can't get enough magnesium from their daily diet may need to take magnesium supplements. However, women should talk with a doctor before taking magnesium supplements while pregnant.
Diarrhea
Usually, magnesium supplements are well tolerated during pregnancy when used as directed. However, mild intestinal irritation may occur and can cause diarrhea. Frequent, watery bowel movements are uncomfortable and may contribute to abdominal cramping, bloating or appetite loss. Pregnant women who experience recurrent bouts of diarrhea may lose too much fluid -- a side effect that may increase the risk of dehydration. If you experience diarrhea for more than two to three days while you are pregnant, contact your doctor.
- Usually, magnesium supplements are well tolerated during pregnancy when used as directed.
- Pregnant women who experience recurrent bouts of diarrhea may lose too much fluid -- a side effect that may increase the risk of dehydration.
Stomach Upset
Side Effects of Magnesium Pills
Learn More
Digestive discomfort, including nausea or vomiting, may develop after taking a dose of magnesium. These side effects may mimic morning sickness, a common symptom associated with pregnancy. Though upset stomach side effects usually subside within a few hours of treatment, seek care from your physician if vomiting is severe or persistent.
- Digestive discomfort, including nausea or vomiting, may develop after taking a dose of magnesium.
- These side effects may mimic morning sickness, a common symptom associated with pregnancy.
Overdose
Improper or excessive use of magnesium supplements may cause severe side effects during pregnancy 3. As a pregnant woman, do not take more than 350 mg of magnesium in supplement form, to limit your risk of overdosing on this mineral. Consuming more than 350 milligrams of magnesium by eating magnesium-rich foods won't cause overdose symptoms. Overdose symptoms include:
- persistent vomiting that lasts more than a few hours
- heart rate irregularities
- breathing difficulties
- muscle weakness
- reduced blood pressure
- confusion
- coma
Seek emergency medical care if you exhibit any of these symptoms, because a magnesium overdose can be deadly without appropriate medical intervention.
- Improper or excessive use of magnesium supplements may cause severe side effects during pregnancy 3.
- Consuming more than 350 milligrams of magnesium by eating magnesium-rich foods won't cause overdose symptoms.
Medication Interactions
Side Effects of Milk of Magnesia
Learn More
Magnesium supplements may interact with other types of medications you may need to take while you are pregnant. Pregnant women who require treatment with antibiotics should be aware that magnesium supplements may reduce the body's ability to absorb antibiotics. To limit this type of interaction, expectant mothers should take magnesium supplements at least one hour before or two hours after taking a dose of antibiotic. Using magnesium supplements in conjunction with blood pressure lowering medications, such as calcium channel blockers, while pregnant may enhance your risk of experiencing the negative side effects associated with antihypertensive drugs. Additional medications that may interact with magnesium during pregnancy include diabetes drugs, levothyroxine, tiludronate and alendronate.
- Magnesium supplements may interact with other types of medications you may need to take while you are pregnant.
- Using magnesium supplements in conjunction with blood pressure lowering medications, such as calcium channel blockers, while pregnant may enhance your risk of experiencing the negative side effects associated with antihypertensive drugs.
Related Articles
References
- University of Maryland Medical Center: Magnesium
- Office of Dietary Supplements: Dietary Supplement Fact Sheet: Magnesium
- Cochrane Database of Systematic Reviews: Magnesium Supplementation in Pregnancy
- Rodríguez-Morán M, Guerrero-Romero F. Oral Magnesium Supplementation Improves Insulin Sensitivity and Metabolic Control in Type 2 Diabetic Subjects: A randomized double-blind controlled trial. Diabetes Care.2003 Apr;26(4):1147-52. doi:10.2337/diacare.26.4.1147
- Office of Dietary Supplements/National Institutes of Health. Magnesium: Fact Sheet for Health Professionals. Bethesda, Maryland; updated July 11, 2019.
- Kass LS, Poeira F. The effect of acute vs chronic magnesium supplementation on exercise and recovery on resistance exercise, blood pressure and total peripheral resistance on normotensive adults. J Int Soc Sports Nut. 2015;12:19. doi:10.1186/s12970-015-0081-z
- Morais JBS, Severo JS, de Alencar GRR, et al. Effect of magnesium supplementation on insulin resistance in humans: A systematic review. Nutrition. 2017 Jun;38:54-60. doi:10.1016/j.nut.2017.01.009
- Rosanoff A, Weaver CM, Rude RK. Suboptimal magnesium status in the United States: are the health consequences underestimated? Nutr Rev. 2012 Mar;70(3):153-64. doi:10.1111/j.1753-4887.2011.00465.x
- Zhang X, Li Y, Del Gobbo LC, et al. Effects of Magnesium Supplementation on Blood Pressure: A Meta-Analysis of Randomized Double-Blind Placebo-Controlled Trials. Hypertension. 2016;68:324-33. doi:10.1161/HYPERTENSIONAHA.116.07664
Writer Bio
Rae Uddin has worked as a freelance writer and editor since 2004. She specializes in scientific journalism and medical and technical writing. Her work has appeared in various online publications. Uddin earned her Master of Science in integrated biomedical sciences with an emphasis in molecular and cellular biochemistry from the University of Kentucky College of Medicine.