The Benefits of Magnesium During Pregnancy

Magnesium is a multi-tasking mineral that supports many processes in the body, making it especially important during pregnancy. From supporting fetal bone and nervous system development to reducing the risk of complications and relieving common pregnancy discomforts, magnesium is one of the most important nutrients to consider throughout pregnancy.

Key benefits of magnesium during pregnancy

1. Supporting fetal growth and development

Magnesium is important for your baby's developing bones, muscles and nervous system. It also supports the healthy formation of DNA and RNA, ensuring that cells grow and divide properly. Adequate magnesium levels are important for preventing growth restrictions and supporting your baby through key developmental milestones.¹

2. Reducing the risk of complications

Magnesium plays a role in maintaining healthy blood pressure, which may reduce the risk of preeclampsia, a potentially serious pregnancy complication. Research also suggests magnesium may help prevent preterm labour by supporting uterine muscle relaxation and reducing the risk of contractions occurring too early.¹

3. Relieving pregnancy discomforts

Pregnancy may bring leg cramps, headaches and muscle discomfort. Magnesium acts as a natural muscle relaxant, helping to ease cramping. It may also support digestive regularity, which is particularly relevant as constipation is a common issue during pregnancy.

4. Supporting sleep and stress management

Hormonal changes and physical discomforts during pregnancy can interfere with sleep and increase stress levels. Magnesium may support relaxation by helping regulate cortisol levels and supporting sleep quality, which has downstream benefits for both maternal and fetal wellbeing.

How much magnesium do you need in pregnancy?

Pregnancy increases magnesium requirements to approximately 350 to 400mg per day. Modern agricultural practices have reduced the magnesium content of many soils, meaning that even a healthy diet may not consistently provide sufficient magnesium. This is one reason why supplementation is commonly recommended alongside a magnesium-rich diet during pregnancy.

Magnesium-rich foods for pregnancy

Including magnesium-rich foods alongside supplementation provides the most reliable approach to meeting requirements. Good dietary sources include:

• Leafy greens: Spinach (79mg per 100g), Swiss chard (81mg per 100g)
• Nuts and seeds: Almonds (270mg per 100g), pumpkin seeds (262mg per 100g)
• Legumes: Black beans (70mg per 100g), lentils (36mg per 100g)
• Whole grains: Quinoa (64mg per 100g), brown rice (43mg per 100g)
• Seafood: Mackerel (97mg per 100g), salmon (26mg per 100g)

Why magnesium supplements may be necessary in pregnancy

While a balanced diet is the foundation of good nutritional health, consistently reaching 350 to 400mg of magnesium per day through food alone can be challenging, particularly if nausea, food aversions or dietary restrictions are affecting your intake during the first trimester.

Zita West Bioactive Marine Magnesium

A marine-derived magnesium supplement providing a high dose alongside trace minerals for greater absorption than standard magnesium supplements alone. Formulated for use during pregnancy and the preconception period.

Shop Zita West Magnesium

Tips for optimising magnesium levels in pregnancy

• Cook with whole ingredients: Choose unprocessed foods including fresh vegetables, whole grains and nuts to maximise your magnesium intake from food.
• Limit caffeine: Caffeine may interfere with magnesium absorption, so reducing intake during pregnancy is worthwhile for both magnesium status and general pregnancy health.
• Stay gently active: Gentle exercise such as yoga or walking may support overall nutrient absorption and helps manage the muscle discomforts that magnesium is often taken to address.

FAQs: magnesium and pregnancy

How much magnesium do I need during pregnancy?

The recommended intake during pregnancy is approximately 350 to 400mg per day. Many women do not consistently meet this through diet alone, which is why a dedicated magnesium supplement is commonly recommended alongside a balanced diet. Zita West Bioactive Marine Magnesium provides a high-dose, well-absorbed form suitable for pregnancy.

Can magnesium help with leg cramps in pregnancy?

Yes. Leg cramps are a common pregnancy complaint and magnesium deficiency is associated with increased muscle cramping. Magnesium acts as a natural muscle relaxant and supplementation may help reduce the frequency and severity of leg cramps during pregnancy, though always discuss any new supplement with your midwife or GP first.

Is magnesium safe to take during pregnancy?

Magnesium is generally considered safe at recommended doses during pregnancy and is an important nutrient for both maternal and fetal health. Always discuss any new supplement with your midwife, GP or healthcare provider before starting during pregnancy.

Can magnesium help with sleep during pregnancy?

Magnesium may support sleep quality by helping regulate cortisol and supporting muscle relaxation. Sleep disturbance is common during pregnancy and magnesium is one of several nutrients that may help, alongside good sleep hygiene practices.

What is the best form of magnesium for pregnancy?

Marine-derived magnesium and magnesium glycinate are among the most bioavailable forms and are generally well tolerated. Magnesium oxide is less well absorbed and is better suited to laxative use than nutritional supplementation. Zita West Bioactive Marine Magnesium uses a marine-derived form alongside trace minerals for enhanced absorption.

Should I take magnesium alongside other pregnancy supplements?

Yes. Magnesium works alongside other key pregnancy nutrients including folate, vitamin D, omega-3 and choline. It is important to review your full supplement routine with a healthcare provider to avoid unnecessary duplication. If you would like personalised guidance on which supplements are right for your situation, book a free 1:1 fertility product consultation with our team.

To learn more about nutrition during pregnancy, read our guide to superfoods for pregnancy here.

References

1. Fanni D et al. (2020). The role of magnesium in pregnancy and in fetal programming of adult diseases. Biol Trace Elem Res. 199(10):3647-3657. PubMed

External references: NHS: Vitamins, supplements and nutrition in pregnancy

This content is for educational purposes only and is not intended to diagnose, treat, or replace medical advice. Always consult your midwife, GP or healthcare provider before starting or changing any supplement during pregnancy.