The benefits of magnesium for a harmonious pregnancy
The pregnancy is a period of profound physiological changes. Pregnancy is a period of profound physiological adaptation. To accompany these transformations and support fetal development, a pregnant woman's diet must be rich in key micronutrients. Among them, Magnesium plays a central role throughout pregnancy and the postpartum period.
Magnesium, an essential mineral during pregnancy
Magnesium is involved in more than 300 enzymatic reactions energy production (ATP), muscle function, nerve transmission, protein synthesis, bone and psychological health [1]. Approximately 50-60 % of the body's magnesium is found in bone; the rest is distributed in muscle and soft tissue, including the brain and nerves [2,3].
During pregnancy, a suitable daily intake helps maintain the physiological balance of mother and fetus.
Recommended magnesium intake during pregnancy and breastfeeding
Needs increase during pregnancy: a 35 mg/d supplement is recommended for pregnant women [4]. Recommended dietary intakes vary according to age [4] :
- 14-18 years 400 mg/d
- 19-30 years 350 mg/d
- 31-50 years 360 mg/d
During breast-feeding, requirements do not increase markedly. magnesium concentration in milk remains relatively stable (≈ 25-35 mg/L), irrespective of maternal diet [4]. A magnesium-rich diet, however, remains relevant for maintaining mineral balance maternal.
The benefits of magnesium for problems specific to pregnancy
Impact of magnesium deficiency during pregnancy
A great deal of research has explored the link between magnesium and pregnancy. Adequate levels of this mineral appear to play a role in reducing a number of discomforts and complications.
- Gestational diabetes: Studies have shown that pregnant women with gestational diabetes have lower levels of total and ionized magnesium [5]. A meta-analysis confirms this phenomenon, which is particularly marked in the third trimester and in European populations [6].
- Hypertension and preeclampsia: In addition, insufficient magnesium levels are associated with an increased risk of high blood pressure during pregnancy and preeclampsia [7,8]. A significant decrease in serum magnesium has been observed in women with preeclampsia.
- Preterm labor and premature delivery: Magnesium plays a role in regulating uterine contractions. Insufficient intake could lead to premature labour due to uterine hyperexcitability [9]. Research also suggests that adequate magnesium intake may reduce the risk of premature birth [10].
Effects of magnesium supplementation during pregnancy
Magnesium supplementation has shown beneficial effects on several aspects of pregnancy:
- Improved glycemic control: Magnesium supplementation contributes to better glycemic regulation in women with gestational diabetes. It reduces fasting blood glucose, improves insulin sensitivity and helps lower LDL and total cholesterol [11,12].
- Reduces leg cramps: Leg cramps are common during pregnancy. Several studies have shown that magnesium can reduce their frequency and intensity, with significant improvement as early as 4 weeks of supplementation [13,14].
- Prevention of high blood pressure : Magnesium helps maintain stable blood pressure during the final weeks of pregnancy [15].
- Reduced risk of preeclampsia A recent meta-analysis showed that oral magnesium supplementation could reduce the risk of preeclampsia. [16]
- Reduced maternal hospitalization and premature delivery: Studies have reported a reduction in maternal hospitalizations and premature deliveries in women receiving additional magnesium intake [17,10].
Effects of magnesium supplementation on the newborn [18].
A number of studies have demonstrated the beneficial effect of magnesium intake in babies whose mothers have received magnesium supplements. A best Apgar score at birtha global indicator of the infant's immediate state of health, was observed, as well as a reduction in fetal stress.
There has also been a reduction in late fetal cardiac decelerations and mild ischemic hypoxic encephalopathy (EHI), both associated with a lack of oxygen around birth.
Finally, magnesium seems to have a protective effect against low birth weight and intrauterine growth retardation (RCIU) [19,20]. A lower risk of stillbirth in the third trimester was also observed in groups receiving this supplementation.
Precautions and limitations of current studies
Although numerous studies suggest the positive effects of magnesium during pregnancy, these results should be interpreted with caution. Effectiveness may vary according to each woman's profile, initial magnesium status and duration of supplementation. As a result, further, larger-scale, methodologically sound research is still needed to confirm these benefits and better identify the women who would benefit most.
How can I ensure a healthy intake of magnesium?
To meet the increased need for magnesium during pregnancy, it is essential to give priority to well-assimilated sources, whether from the diet or through appropriate supplementation. However, dietary intake alone may prove insufficient, especially in cases of severe stress [21] or digestive disorders that may reduce intestinal absorption. A combined approach, combining a varied, magnesium-rich diet to dietary supplements well-chosen - especially in the form of bisglycinate or magnesium citrate, renowned for their excellent bioavailability - is often recommended.
Dietary sources of magnesium
Magnesium is naturally present in (values per 100 g of food - source CIQUAL) https://ciqual.anses.fr) :
- Cocoa powder approx. 500 mg
- Dark chocolate (≥70 %): approx. 200 mg
- Oilseeds (almonds, walnuts, hazelnuts): 200 mg
- Sesame and flax seeds 325-370 mg
- Green vegetables (spinach, cabbage): 25-75 mg
- Legumes (chickpeas, white beans - cooked): 16-63 mg
- Oily fish (mackerel): 30 mg/100 g
- Wholegrain cereals (wholemeal bread, oat bran): up to 115 mg
- Dried fruit (dried banana): 108 mg
A varied, plant-rich diet is therefore essential to guarantee an adequate intake.
Magnesium-rich foods also provide valuable vitamins and minerals. vitamins and mineralssuch as calcium, potassium, iron and zinc.
Magnesium supplementation can also prove invaluable for pregnant women whose dietary intake is inadequate, or in cases of increased need linked to a vulnerable terrain (stress, anxiety, persistent fatigue, etc.).
Which form of magnesium is best?
Not all forms of magnesium are created equal. Among the most recommended are magnesium bisglycinate (chelated with glycine) and magnesium citrateappreciated for their excellent bioavailability and their good digestive tolerance [22].
In all cases, before considering supplementation, it is advisable to seek the advice of a health professional, especially if you are taking medication.
To find out more, read our dedicated articles: [Magnesium bisglycinate, a precious ally for everyday energy] and [Magnesium and sleep: how this mineral can transform your nights].
Should I take magnesium supplements while breast-feeding?
Unlike during pregnancy, magnesium requirements do not increase significantly during breastfeeding, although some magnesium is lost via the mother's milk [4]. The concentration of magnesium in breast milk is stable at between 25 and 35 mg/L, irrespective of the mother's diet. The maternal body seems to compensate this loss effectively, notably through increased bone resorption, which can provide magnesium for milk production.
However, this mobilization of bone magnesium can raise questions, particularly in cases of inadequate dietary intake or already compromised body reserves (e.g. after pregnancy or in the presence of chronic stress). This is why it's a good idea to encourage a magnesium-rich diet during breastfeeding, and to consider targeted supplementation if necessary. This not only supports milk production, but also preserve the mother's mineral balance and bone capital.
Magnesium plays a key role during pregnancy and breastfeeding
In short, the magnesium is a fundamental nutrient during pregnancy and breastfeeding. It contributes not only to the well-being of the mother-to-be, but also to the harmonious development of the baby. A varied diet, enriched with foods naturally rich in magnesium, combined if necessary with high-quality supplementation, is a valuable nutritional strategy throughout pregnancy.
References
Physiological role of magnesium
[1] Volpe SL. Magnesium in disease prevention and overall health. Adv Nutr. 2013, 4, 378S.
[2] Uwitonze AM et al. Role of magnesium in vitamin D activation and function. J. Am. Osteopath. Assoc. 2018; 118, 181.
[3] Jomova K, et al. Essential metals in health and disease. Chem Biol Interact. 2022, 367, 110173.
Magnesium and pregnancy
[9] Durlach J, et al. New data on the importance of gestational Mg deficiency. Magnes Res. 2004, 17, 116.
[17] Spätling L, et al. Magnesium supplementation in pregnancy. A double-blind study. Br J Obstet Gynaecol. 1988, 95, 120.
[18] Makrides M, et al. Magnesium supplementation in pregnancy. Cochrane Database Syst Rev. 2014, 2014, 4, CD000937.
[19] Zarean E, et al. Effect of Magnesium Supplement on Pregnancy Outcomes: A Randomized Control Trial. Adv Biomed Res. 2017, 3, 109.
Magnesium requirements during pregnancy and breastfeeding
[4] Institute of Medicine (US) Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington (DC): National Academies Press (US); 1997. PMID: 23115811.
Magnesium and gestational diabetes
[5] Bardicef M, et al. Extracellular and intracellular magnesium depletion in pregnancy and gestational diabetes. Am J Obstet Gynecol. 1995, 172, 1009.
[6] Ren Q, et al. The Association Between Serum Magnesium Levels and Gestational Diabetes Mellitus: a Systematic Review and Meta-Analysis. Biol Trace Elem Res. 2023, 201, 5115.
[11] Luo L, et al. The efficacy of magnesium supplementation for gestational diabetes: A meta-analysis of randomized controlled trials. Eur J Obstet Gynecol Reprod Biol. 2024, 293, 84.
[12] Tan X, et al. Magnesium supplementation for glycemic status in women with gestational diabetes: a systematic review and meta-analysis. Gynecol Endocrinol. 2022, 38, 202.
Magnesium, hypertension and preeclampsia
[7] Zarean E, et al. Effect of Magnesium Supplement on Pregnancy Outcomes: A Randomized Control Trial. Adv Biomed Res. 2017, 6, 109.
[8] Wynn A, et al. Magnesium and other nutrient deficiencies as possible causes of hypertension and low birthweight. Nutr Health. 1988, 6, 69.
[15] Bullarbo M, et al. Magnesium supplementation to prevent high blood pressure in pregnancy: A randomised placebo control trial. Arch Gynecol Obstet. 2013, 288, 1269.
[16] J. Yuan, Y. et al. Oral Magnesium Supplementation for the Prevention of Preeclampsia: a Meta-analysis or Randomized Controlled Trials. Biol. Trace Elem. Res. 2022, 200, 3572.
Effects of supplementation on cramps
[13] Dahle LO, et al. The effect of oral magnesium substitution on pregnancy-induced leg cramps. Am J Obstet Gynecol. 1995, 173, 175.
[14] Supakatisant C, et al. Oral magnesium for relief in pregnancy-induced leg cramps: a randomised controlled trial. Matern Child Nutr. 2015, 11, 139.
Effects on newborn well-being
[10] Zhang Y, et al. Magnesium levels in relation to rates of preterm birth: a systematic review and meta-analysis of ecological, observational, and interventional studies. Nutr Rev. 2021, 79, 188.
[20] Roman A, et al. Maternal magnesium supplementation reduces intrauterine growth restriction and suppresses inflammation in a rat model. Am J Obstet Gynecol. 2013, 208, 383.
Stress, absorption and choice of magnesium form
[21] Pickering G et al. Magnesium Status and Stress: The Vicious Circle Concept Revisited. Nutrients. 2020, 12, 3672
[22] Amiri S. Which magnesium to choose? Nutrition, published on 29/07/2015, updated on 29/03/2022.
Authorized health claims for magnesium
Magnesium contributes to :
- reduce fatigue,
- electrolyte balance,
- normal energy metabolism,
- normal functioning of the nervous system,
- normal muscle function,
- normal protein synthesis,
- normal psychological functions,
- maintenance of normal bone structure,
- maintenance of normal dentition.
Magnesium plays a role in the cell division process.
