Pregnancy: The Essential Guide to Vitamins and Minerals

Many women take multivitamins during pregnancy to meet their nutritional needs. But the truth is that standard multivitamins rarely cover all essential nutrients, especially iron, vitamin D, calcium, and certain trace elements.

In this blog, you will learn:

• The essential nutrients and their roles

• Recommended daily doses and food sources

• When supplementation is necessary

• Whether diet alone can be sufficient

• Why folate (folic acid) is crucial

• How to adjust supplementation based on blood tests, diet, and individual risk factors

Nutrient

Main Role

Recommended Intake During Pregnancy

Typical Multivitamin Content

Food Sources

Can Diet Alone Cover?

Notes / Supplementation if Needed

Folate / Folic Acid

Prevents neural tube defects

400–800 µg/day

~400 µg/day

Spinach, broccoli, legumes, oranges, whole grains

Often insufficient

Multivitamin supplementation essential, especially pre-conception and 1st trimester

Iron

Prevents anemia, supports red blood cell production

27 mg/day prophylactic, 80–160 mg/day if deficient

15–18 mg/day

Red meat, chicken, fish, lentils, beans, spinach

Rarely sufficient if deficient

Take with vitamin C for better absorption, avoid with milk

Calcium

Bones, teeth, muscles, blood clotting

1000 mg/day

Often absent or low

Milk, yogurt, cheese, leafy greens, sesame

Possible if diet rich

Supplement if low dairy intake, vegetarian/vegan diet, BMI <18.5, history of preeclampsia or hypertension

Vitamin D

Calcium absorption, bones, immunity

600–800 IU/day, 2000–4000 IU/day if deficiency

200–600 IU/day

Fatty fish, eggs, liver, fortified dairy, sunlight

Rarely sufficient

Supplement targeted after blood test; standard multivitamins usually too low

Folate – the most important from the start

• Role: prevents neural tube defects in the baby

• Recommended dose: 400–800 µg/day, ideally before pregnancy

• Food sources: spinach, broccoli, legumes, oranges, whole grains

• Note: Diet alone is often insufficient → suitable multivitamins are essential

Iron – often needs supplementation

• Role: prevents anemia, supports red blood cell production

• Prophylactic dose: 27 mg/day

• If deficiency is confirmed: 80–160 mg/day depending on Hb and ferritin

• Food sources: red meat, chicken, fish, lentils, beans, spinach

• Tip: take with vitamin C for better absorption, avoid taking with milk

Vitamin D – supplementation almost always needed

• Practical observation: very few patients have normal vitamin D levels

• Dose if deficient or insufficient: 2000–4000 IU/day

• Food sources: fatty fish, eggs, liver, fortified dairy products, sunlight

• Why standard multivitamins are insufficient: they usually contain only 400–600 IU

Calcium – when to supplement

• Recommended intake: 1000 mg/day

• Food sources: milk, cheese, yogurt, leafy greens, sesame

• Supplementation is necessary if:

  • low intake of dairy products

  • vegetarian or vegan diet

  • BMI <18.5 (risk of low bone density)

  • history of preeclampsia, hypertension → studies show possible protective effect

Other components of multivitamins: trace elements

Trace element	Main role	Recommended pregnancy intake	Food sources	Can diet alone cover it?	Notes / supplementation if needed
Zinc	Growth, healing, immune system	11–12 mg/day	Meat, fish, eggs, legumes, nuts	Often sufficient	Supplement only if deficiency
Copper	Iron metabolism, red blood cells	1 mg/day	Liver, nuts, seeds, legumes	Usually sufficient	Supplement if dietary deficiency
Selenium	Antioxidant, thyroid function	60 µg/day	Brazil nuts, fish, eggs, cereals	Often sufficient	Supplement if diet poor
Iodine	Thyroid hormones, fetal brain development	220 µg/day	Iodized salt, fish, dairy	Varies depending on iodized salt intake	Supplement if low intake
Manganese	Metabolism, bone formation	2 mg/day	Whole grains, nuts, vegetables	Generally sufficient	Supplement only if deficient

Note: High doses of vitamin A (retinol) can be toxic → prefer beta-carotene.

Changing multivitamins by trimester

• 1st trimester: focus on folate and vitamin D, moderate iron

• 2nd and 3rd trimesters: iron and calcium may be increased if needed

• Practical tip: it’s not always necessary to change brand – better to adjust supplements based on blood tests and diet

Practical checklist: Is my multivitamin adequate?

✅ Contains folate 400–800 µg/day

✅ Iron sufficient: 27 mg prophylactic, 80–160 mg if deficient

✅ Vitamin D: 600–800 IU standard, 2000–4000 IU if deficient

✅ Calcium 1000 mg/day if diet insufficient or at risk

✅ No high-dose retinol, prefer beta-carotene

✅ Trace elements present, but usually in low doses

Conclusion

Standard multivitamins often cover only the minimum requirements. Folate, iron, vitamin D, and calcium often need special attention and targeted supplementation, especially if blood tests show a deficiency or diet is inadequate. Trace elements can be useful, but do not replace the essential supplements needed for these key nutrients.

Take care of yourself,

Dr. Sandra Yene Amougui