Positive pregnancy test on a blue background to highlight link between B12 status and pregnancy outcomes

Roles of vitamin B12 during pregnancy

Medically reviewed on May 17, 2022 by Jordan Stachel, M.S., RDN, CPT. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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Think about how much work the body does when pregnant —and because you’re growing a whole new human, healthy habits are important. This includes eating well-rounded, nutritious meals packed with essential vitamins.

B complex vitamins are one group of vitamins that are crucial for a healthy pregnancy. Eight total B vitamins make up the B complex vitamin group, including B12 [1]. While vitamin B12 is essential for normal body functions in all of us, this vitamin is particularly important for individuals who are pregnant.

Keep reading to learn more about why adequate levels of vitamin B12 are a must during all stages of pregnancy. (If you're looking to increase your B12 intake, learn more about Everlywell vitamin B12 supplements.)

1. Brain and spine development

The first vitamin B12 pregnancy connection results from the role B12 plays in brain and spine development. In fact, your baby’s brain and spinal cord require sufficient levels of B12 to grow.

This essential prenatal vitamin pairs with two other B complex vitamins for brain and spinal growth, including [2]:

  • Vitamin B-1 (thiamine)
  • Vitamin B-6 (pyridoxine)

Together, these three B vitamins help ensure that your baby’s spine and brain develop normally.

2. Nervous system health

Vitamin B12 supplementation is also essential for your nervous system health and that of your developing fetus’ nervous system. There are several ways vitamin B12 supplements impact the nervous system. These include [3]:

  • The synthesis of RNA and DNA in the cell’s nucleus
  • Prevention of nervous system development disorders
  • Maintenance of cognitive health

Without sufficient levels of B12, you and your child may suffer serious nervous system ramifications, such as problems with vision, issues with memory, or difficulty walking, among other potential symptoms [4].

3. Energy and mood

Vitamin B12 plays a crucial role in maintaining your energy levels and mood regulation as well [5]. In fact, an insufficient amount of B12 in the diet can mean plummeting energy levels.

Compounded with hormonal shifts, a deficiency during early pregnancy can negatively impact mood and ability to perform daily functions.

4. Prevention of some birth defects

Remember when we noted that there are eight B complex vitamins? Although we’ve focused primarily on the role of B12, another B vitamin—vitamin B9, also known as folic acid—can work with B12 to make it even more beneficial.

When paired with folic acid, vitamin B12 may help prevent certain birth defects from occurring in an unborn child, making this vitamin a must for all pregnant individuals.

The specific disorders vitamin B12 and vitamin B9 may help prevent are called Neural Tube Defects (NTD), and they include [6]:

  • Spina bifida – Spina bifida is the result of incorrect spinal cord development. This defect forms during early pregnancy if the spinal column doesn’t fully grow or close.
  • Encephalocele – Encephalocele occurs when the neural tube doesn’t close completely during pregnancy. The result is a bulge at the back of the head containing brain tissue and spinal fluid. This birth defect can be life-threatening for a baby.
  • Anencephaly – Anencephaly is a condition in which the baby is born without parts of the skull and brain. Unfortunately, almost all babies born with this condition die shortly after birth.

Where do you get vitamin B12 in your diet?

If you're pregnant, you’re probably wondering which foods you can eat to help ensure you’re getting enough vitamin B12 intake daily. Some of the richest sources of this essential vitamin include [5]:

  • Beef and turkey
  • Salmon and tuna
  • Clams
  • Strawberries and bananas
  • Spinach
  • Kidney beans
  • Nutritional yeast
  • Eggs
  • Fortified cereals
  • Mile, cheese, and yogurt

For that extra beneficial dose of B9, you can add the following foods to your diet [7]:

  • Beef
  • Spinach and other leafy greens
  • Rice
  • Kidney beans
  • Fortified cereals
  • Orange juice
  • Broccoli and brussels sprouts
  • Bananas, papayas, and oranges
  • Eggs

As you can see, many foods rich in B12 are also good sources of B9. This means you can double down on B-vitamin benefits when you eat foods containing both.

B12 and prenatal vitamins

Most prenatal vitamins contain the B complex vitamins essential for a healthy pregnancy. However, in some cases, a healthcare professional may recommend that you take additional vitamin B12 supplements.

According to the American Pregnancy Association, individuals who may need more B12 include [8]:

  • Those deficient in B12 before pregnancy
  • Vegetarians or vegans
  • Those with medical conditions that prevent sufficient nutrient absorption
  • Anemic individuals

If you have any of these conditions, you might need extra B12 supplementation for a healthy pregnancy.

B12 supplements from Everlywell

Any pregnancy can significantly benefit from a nutritious diet rich in all the essential vitamins. Vitamin B12 is especially important for pregnant individuals since sufficient levels of B12 are necessary for fetal brain and spine development, the prevention of some birth defects, and more. So if you're looking to give your B12 intake a boost, try Everlywell B12 vitamin supplements for an easy option. The tablets are vegan and non-GMO, and each bottle comes with a 30-day supply of B12.

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1. B Vitamins. MedlinePlus. URL. Accessed May 17, 2022.

2. B Vitamins and Folic Acid. National Health Service. URL. Accessed May 17, 2022.

3. Reynolds E. Vitamin B12, folic acid, and the nervous system. Lancet Neurol. 2006 Nov;5(11):949-60.

4. Complications. National Health Service. URL. Accessed May 17, 2022.

5. Vitamin B12 Fact Sheet. National Institutes of Health. URL. Accessed May 17, 2022.

6. O'Leary F, Samman S. Vitamin B12 in health and disease. Nutrients. 2010;2(3):299-316.

7. Folate. National Institutes of Health. URL. Accessed May 17, 2022.

8. Roles of Vitamin B in Pregnancy. American Pregnancy Association. URL. Accessed May 17, 2022.

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