Roles of Vitamin B in Pregnancy

vitamin b during pregnancy

Maintaining a healthy balanced diet at all stages of life is important, but when you’re pregnant you have even more reason to take care of your body and ensure your little one grows into a healthy, bouncing baby!

B vitamins, which you’ll often hear referred to as vitamin B complex, are particularly important aspects of your nutrition during pregnancy, especially vitamins B-6, B-9 and B-12 which all help to minimize the risk of birth defects as well as relieve some symptoms of pregnancy.

This is why taking quality prenatal vitamins is a great way to assure you are getting all the vitamins you and baby need for a healthy pregnancy.

Crucial Roles of Vitamin B in a Healthy Pregnancy

The entire B complex of eight vitamins plays a crucial role in your strength and health while your baby is developing. During your first and third trimesters, most women feel more tired and run down than usual.

Although, the best way to absorb these nutrients is through vitamin rich foods!

Vitamin B rich foods help boost your natural energy by ensuring your diet is packed with these nourishing vitamins for your growing baby. Take a look at the roles and benefits of all the B vitamins and find out how to get enough of each to ensure a happy, healthy pregnancy.

Vitamin B-1: Thiamine

Since Thiamine plays a major role in the development of your baby’s brain, you need to be aiming to consume 1.4 mg of vitamin B-1 every day. Below are brilliant natural sources of vitamin B-1, so incorporate these foods into your diet to keep your baby’s brain development healthy.

Natural Food Sources of Vitamin B1:

  • Peas
  • Oats
  • Pork
  • Lentils
  • Pecans
  • Salmon
  • Brazil Nuts
  • Dried Beans
  • Wheat Germ
  • Nutritional Yeast
  • Whole Grain Pasta
  • Fortified Breads or Cereals

Vitamin B-2: Riboflavin

Riboflavin is essential for good eye health and it has the added benefit of giving your skin a fresh, healthy glow – cue the compliments from friends and family about how great you look during your pregnancy! This is also true for your baby.

As with all B vitamins, though, riboflavin is water soluble and therefore not stored in your body, which means you need to get a good, healthy dosage of around 1.4 mg each when pregnant compared to the usual 1.1 mg for non-pregnant women.

Whole grains, fortified foods as well as Dark and leafy green veggies are great rich sources of vitamin B2.

Natural Food Sources of Vitamin B2:

  • Almonds (roasted is an excellent source)
  • Sweet Potatoes
  • Carrots
  • Oats
  • Peas
  • Tempeh
  • Broccoli
  • Spinach
  • Fenugreek
  • Asparagus
  • Mushrooms
  • Whole Grains
  • Nutritional Yeast
  • Fortified Cereals
  • Brussels Sprouts
  • Cheese, Cottage, Ricotta, Milk, Eggs, Natural Yogurt
  • Wild Salmon (highest concentration of B2 found in animal sources)
  • Pork, Chicken, Beef (Liver and Kidney offers high amounts)

What Vitamin B2 Aids In Pregnancy

  • promotes good vision, healthy skin, the development and growth of baby’s bones, muscles, and nerves.
  • lowers risk of developing preeclampsia, a pregnancy complication
  • Signs You Do Not Get Enough Vitamin B2

Riboflavin deficiency signs include anemia, magenta (dry and red tongue), skin rash, dermatitis, dryness and cracking around mouth, nose, and lips. You also have a B2 deficiency risk if you are lactose intolerant or anorexic. Be sure you are eating nutrient rich foods or taking a prenatal vitamin.

If you are dealing with an eating disorder while pregnant, we are here to help you!

Contact a professional at the American Pregnancy Association by calling 1-800-672-2296 M-F 10am-6pm to discuss your concerns, get resources or to ask questions about your pregnancy.

Vitamin B3: Niacin

Vitamin B-3 has a whole host of benefits for your body; it can improve digestion, reduce nausea and take the edge off debilitating migraines. Aim for around 18 mg every day. Sunflower and chia seeds are high in B3, along with organ meats and tuna but too much of the wrong tuna during pregnancy can expose you to high levels of mercury. This is why the American Pregnancy Association stands behind, Safe Catch Elite canned tuna. Below are more natural sources of vitamin B3.

“Intake of more than 35 mg has not been studied in pregnant women” – Merck Manuals Online Medical Library

Therefore it is not recommended for pregnant women to consume doses larger than 18 mg of vitamin B3 when it comes to supplementation.

Natural Food Sources of Vitamin B3:

  • Turkey
  • Venison
  • Wild Salmon
  • Chicken Breast
  • Peanuts
  • Crimini Mushrooms
  • Liver
  • Tuna
  • Peas
  • Tahini
  • Kidney Beans
  • Grass-fed Beef
  • Sunflower Seeds
  • Avocados
  • Asparagus
  • Tomatoes
  • Bell Peppers
  • Sweet Potato
  • Brown Rice

How Vitamin B3 Aids In Pregnancy

  • Essential for your baby’s brain development
  • Keeping nervous systems, mucous membranes and skin healthy
  • Improves digestion, eases nausea and can relieve painful migraines

What You Must Know About Vitamin B3 During Pregnancy

Niacin is one you do not want to have vitamin overdose during pregnancy on. If you are on a niacin supplement before your pregnancy, you need to speak to your doctor about stopping the supplementation while you are pregnant and taking prenatal vitamins.

Vitamin B5: Pantothenic Acid

Pregnancy can do some strange and frustrating things to our bodies, one of which is painful leg cramps. Luckily, vitamin B5 can help to ease these cramps, so aim to consume 6 mg every day. It also has the added benefit of producing important pregnancy hormones.

Whole grains and fortified cereals are a fabulous source for B5 so that’s breakfast covered, but you’ll also find the vitamin in egg yolks, brown rice, cashew nuts, and broccoli, all of which are perfect ingredients for a delicious and nutritious stir fry! Below are several other sources of B5.

Natural Food Sources of Vitamin B5:

  • Sunflower Seeds
  • Sweet Potato
  • Avocado
  • Whole Grains or Fortified Cereals
  • Crimini Mushrooms
  • Oats
  • Organic Corn
  • Cauliflower
  • Wild Salmon
  • Chicken Breast
  • Milk
  • Oranges
  • Banana
  • Sun-dried Tomatoes
  • Trail Mix (Seeds, Nuts and Chocolate Chips)

What Vitamin B5 Aids In Pregnancy

  • Helps metabolize fats, proteins, and carbohydrates
  • Helps to prevent pregnancy-related muscle cramps
  • Helps the releasing of stress relieving hormones

Vitamin B6: Pyridoxine

Pyridoxine is vital for the development of your baby’s nervous system and brain throughout the whole 9 months of your pregnancy week by week, but it has some wonderful beneficial side effects for you, too.

Part of its role in the body is to produce norepinephrine and serotonin, two essential neurotransmitters which aid a whole host of metabolic functions. Vitamin B6 during pregnancy can also help to alleviate nausea and vomiting which are perhaps two of the very worst side effects of pregnancy, particularly in the early stages.

To maximize the health of both you and baby, you should consume between 25 and 50 mg of vitamin B6 each.

However, despite it being a very safe vitamin to consume, doctors recommend not to exceed the daily dose; in this case, more isn’t better.

You can find B6 in beans, bananas, papayas whole grain cereals and several other natural food sources great for pregnancy smoothies rich in B6.

Natural Food Sources of Vitamin B6:

  • Garlic
  • Beans
  • Sweet Potatoes
  • Chickpeas
  • Avocados
  • Hazelnuts
  • Sunflower Seeds
  • Brown Rice
  • Prune Juice
  • Spinach
  • Bananas
  • Papaya
  • Chicken
  • Pork Loin
  • Wild Salmon
  • Turkey
  • Grass-fed Beef
  • Safe-Catch Elite Tuna

How Vitamin B6 Aids In Pregnancy

  • Helps to prevent low birth weight
  • Essential to the development of your baby’s brain and nervous system
  • Helps maintain blood glucose at healthy levels
  • May help with morning sickness

What You Must Know About Vitamin B6 During Pregnancy

Vitamin B6 in excess amounts can lead to numbness and nerve damage. Be sure you know the amount supplied in your prenatal vitamin and the amount in your diet does not exceed 300 mg per day.

Vitamin B7: Biotin

Pregnancy often causes a deficiency in vitamin B7, so make sure you’re eating plenty of biotin-rich foods such as oats, milk, mushrooms and Swiss Chard. The US Food and Nutrition Board of the National Academy of Science’s Institute of Medicine recommends 30 mcg of vitamin B7 for pregnant women.

If you’re planning on breastfeeding, note that the recommended intake for nursing moms is 35 mcg, so you may need to slightly increase your intake when your little bundle of joy arrives.

Natural Food Sources of Vitamin B7:

  • Oats
  • Avocado
  • Spinach
  • Broccoli
  • Cauliflower
  • Legumes
  • Royal Jelly
  • Fortified Cereal
  • Brewer’s Yeast
  • Blackstrap Molasses
  • Swiss Chard
  • Wild Salmon
  • Mushrooms
  • Wheat Bran
  • Cheese
  • Raspberries
  • Cauliflower
  • Egg Yolk
  • Chicken
  • Potatoes
  • Soy
  • Milk
  • Nuts
  • Liver
  • Pork

What Vitamin B7 Aids In Pregnancy

  • Helps hair loss, brittle nails, and skin rashes
  • Essential to embryonic growth during your pregnancy

Signs You Do Not Get Enough Vitamin B7

Vitamin B7 deficiencies can cause many symptoms like listlessness, depression, hair thinning, tingling sensations in legs and arms or hallucinations.

What You Must Know About Vitamin B7 During Pregnancy

Too large doses of biotin over long periods of time could lead to rare side effects like allergies, acne or miscarriages during pregnancy. These side effects are rare but always consult with your OBGYN when it comes to prenatal vitamins and your diet.

Vitamin B9: Folic Acid

It’s fairly common knowledge that folic acid is one of the most important B vitamins to take during pregnancy and for very good reason. Folic acid reduces the risk of your baby developing neural tube birth defects like spina bifida, and it’s also responsible for helping to produce red blood cells which are obviously important for both you and your growing baby.

You should be consuming at least 400 mg of vitamin B9 every day throughout your entire pregnancy. If you’re trying to conceive it’s also recommended that you consume this same amount of folic acid to maximize your chances of getting pregnant.

However, generally, it is recommended to take daily prenatal vitamins which contain at least 600 mg of folic acid, just to make sure you’re definitely getting enough. On top of this, try to increase your consumption of foods which naturally contain the vitamin.

Folic Acid Dosages Breakdown

  • 400 mg a day if you are trying to conceive
  • 400 mg a day during the First Trimester
  • 600 mg a day from four months to nine months

Lentils, citrus fruits, particularly oranges and grapefruits, are high in folic acid, as are dark green veggies like spinach, broccoli, and asparagus.

Natural Food Sources of Vitamin B9:

  • Lentils
  • Spinach
  • Great Northern Beans
  • Fortified Cereals
  • Asparagus
  • Avocado
  • Peas
  • Nuts
  • Dried Beans
  • Egg Noodles
  • Beef Liver
  • Sprouts

What Vitamin B9 Aids In Pregnancy

  • Preventing NTDs (neural tube defects) like anencephaly (a brain defect) or spina bifida (spinal cord defect). NTDs can develop at the earliest stage of pregnancy, so it is important to be consuming folic acid from the time you start trying to conceive.
  • Reduces risks to birth defects like cleft lip, cleft palate, some heart defects
  • Reduces the risk of preeclampsia during pregnancy
  • Important for the growth of the placenta, synthesis of DNA and the development of the baby
  • Essential for red blood cell production and helps prevent forms of anemia

The majority of prenatal vitamins supply 800 – 1,000 mg of vitamin B9. Be sure to not consume any more than 1,000 mg a day, unless you are advised by your doctor.

When Do You Need Extra Vitamin B9?

  • Those pregnant with twins, your doctor could have your take 1,000 mg daily
  • Overweight women may need more than 400mg a day, ask your doctor before you become pregnant and before you take extra
  • Those taking anti-seizure or diabetes meds may be told to take more daily
  • If your developing baby has already developed an NTD, your doctor may have you take 4,000 mg daily
  • If you have Methylenetetrahydrofolate reductase, a genetic mutation that makes it harder to produce folic acid (folate) in your body

It is important you understand all the prenatal vitamin limits when choosing your prenatal vitamins.

Vitamin B12: Cobalamin

Vitamin B12 is important for maintaining the health of your nervous system, but it’s also believed that when combined with folic acid during pregnancy, B12 supplements can help to prevent spina bifida and other spinal and central nervous system birth defects in your baby, too.

You can find B12 in fortified foods (soy or soy milk), fish, poultry, eggs and milk and should aim for around 2.6 mg per day, but using supplements to achieve this intake will help.

Natural Food Sources of Vitamin B12:

  • Wild Salmon
  • Soy Milk or Soy Products (fortified with B12 on the label)
  • Shrimp
  • Grass-fed Beef Liver or Tenderloin
  • Yogurt
  • Fortified Cereals
  • Red Meat
  • Swiss Cheese
  • Milk
  • Cottage Cheese
  • Cod

How Vitamin B12 Aids In Pregnancy

  • Essential for baby’s neural tube formation, brain and spine development
  • Together with Folate (B9), it works to produce DNA synthesis and red blood cells
  • Aids the development and functioning of your brain, nerves and blood cells
  • Helps improve your energy, mood and stress levels by aiding the metabolization of fats, carbohydrates, and proteins.
  • Helps maintain normal central nervous system and neurological functions by regulating synthesis of myelin and fatty acids.

Signs You Do Not Get Enough Vitamin B12

For women in childbearing age, B12 deficiencies are quite rare, if they occur it increases a risk of your developing baby getting a NTDs or Neural Tube Defect.

These serious birth defects can include:

  • Anencephaly – the spinal cord and brain do not form properly
  • Encephalocele – parts of the brain begins to push out
  • Spina bifida – the baby’s spine does not form correctly

If any of these birth defects run in the family a triple screen test will be necessary.

Find a Genetic Counselor in your area

If you believe you may have a vitamin B12 deficiency and are suffering from depression, anxiety, fatigue or insomnia, contact your doctor immediately.

Brain damage can occur in severe deficiency conditions, it is very important you share all your concerns with your doctor to prevent any vitamin deficiencies from causing damage to your body or your developing baby’s body.

Do You Need a B12 Supplement?

Your doctor may ask you to supplement B12 with folic acid if you are vitamin B12 deficient before pregnancy. Both of these supplements together will help prevent birth defects in developing babies as well as helps combat defects that affect the spine and central nervous system. Prenatal vitamins should help with most deficiencies, ask your doctor if you have any questions.

Vitamin B Roles For Pregnancy Cheat Sheet

Here’s a handy cheat sheet to help you remember exactly how each B vitamin can support you and your growing baby throughout pregnancy.

  • B-1 (Thiamine): 1.4 mg – Supports baby’s healthy brain development
  • B-2 (Riboflavin): 1.4 mg – Keeps eyes healthy and skin glowing
  • B-3 (Niacin): 18 mg – Eases morning sickness, keeps nausea at bay and improves digestion
  • B-5 (Pantothenic Acid): 6 mg – Reduces leg cramps and helps produce essential pregnancy hormones
  • B-6 (Pyridoxine): 25 – 50 mg – Aids the development of baby’s nervous system and brain
  • B-7 (Biotin): 30 mcg – Deficiency is often caused by pregnancy, so increased consumption is vital
  • B-9 (Folic Acid): 400 – 600 mg – Plays huge role in reducing the risk of birth defects
  • B-12 (Cobalamin): 2.6 mg – Maintains and supports the development of you and your baby’s nervous system

B Vitamin Complex Supplements During Pregnancy

Typically, prenatal vitamins contain the perfect blend of B vitamin complex to fulfill all the recommended dosages we’ve outlined here. There’s no need to routinely supplement any B vitamins other than taking your prenatal vitamin; simply enjoy a well-balanced diet alongside it and look forward to the arrival of your little one!

If you have any questions be sure to ask your OBGYN. You and your developing baby’s health depend on you asking questions, staying healthy and stress-free. Enjoy being pregnant, and eat healthy for two.

Last updated: February 8, 2017 at 12:50 pm


Compiled using information from the following sources:

1. MRC Vitamin Study Research Group. Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet. 1991; 338:131–137.

2. Biotin. (2017, Jan 10).

https://www.nlm.nih.gov/medlineplus/druginfo/natural/313.html

3. Pitkin RM. Folate and neural tube defects. Am J Clin Nutr. 2007; 85:285S–288S.

4. Harvard’s Nutrition Source on Vitamin B.

https://www.hsph.harvard.edu/nutritionsource/vitamin-b/

5. Food sources of riboflavin.

http://www.dietitians.ca/Downloads/Factsheets/Food-Sources-of-Riboflavin.aspx

6. Scott, J. M. (n.d.). Addition of vitamin B12 to folic acid supplements to optimize the prevention of spina bifida and other neural tube defects.

http://www.shinecharity.org.uk/uploads/media_items/professor-scott-s-report-for-shine.original.pdf

7. Shrim, A., Boskovik, R., Maltepe, C., et al. Pregnancy outcome following use of large doses of vitamin B6 in the first trimester. Journal of Obstetrics & Gynaecology, 26(8), 749-51.

http://www.ncbi.nlm.nih.gov/pubmed/17130022

8. Paediatr Perinat Epidemiol. 2012 Jul;26 Suppl 1:55-74. doi: 10.1111/j.1365-3016.2012.01277.x. Interventions with vitamins B6, B12 and C in pregnancy.

https://www.ncbi.nlm.nih.gov/pubmed/22742602

9. U.S. Department of Health and Human Services. NIH. National Institutes of Health. Office of Dietary Supplements: Vitamin B

https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/

10. The Motherisk Program, Division of Clinical Pharmacology/Toxicology, Hospital for Sick Children, University of Toronto, Ontario, Canada. “Pregnancy outcome following use of large doses of vitamin B6 in the first trimester”

https://www.ncbi.nlm.nih.gov/pubmed/17130022