The Best Prenatal Vitamins and When to Start Taking Them

Dr. Jolene BrightenPublished: Last Reviewed: Pregnancy Leave a Comment

When it comes to preconception care, getting pregnant naturally, and having a health pregnancy, taking the best prenatal vitamins is a must. In general, it is recommended that women begin taking a prenatal well in advance of trying to conceive.

They’re also often taken by women who aren't planning on becoming pregnant because they can help create luscious, shiny hair and glowing skin. 

But did you know that the type of prenatal vitamin you choose, and when you start taking it, play an important role in your pregnancy? As a women's health naturopathic physician I recommend women begin a prenatal at least six months prior to conception and continue it through breastfeeding.

The Best Prenatal Vitamins Include:

  1. Folate is necessary to protect the rapidly dividing cells of the baby. Deficiency = damage to your reproductive cells. You want folate, not folic acid. Folic acid can be problematic for women with methylation issues. It is also not the highest quality version of this vitamin. Folate is well recognized for its role in preventing neural tube defects. While most multivitamins include 400 micrograms, many experts recommend 800 micrograms during pregnancy.
  2. B12 low levels have been associated with miscarriage & infertility.
  3. B6 is necessary for supporting your luteal phase, which is when your body gets primed for implantation.
  4. Vitamin C helps your body make progesterone, which is necessary for maintaining a pregnancy (& safe guarding against PMS).
  5. Vitamin E protects your eggs from free radical attacks that would damage them.
  6. Zinc necessary for making superoxide dismutase, an enzyme that keeps your eggs healthy.
  7. Copper is also important for supporting antioxidant production and needs to be in balance with zinc.
  8. Magnesium is necessary for fertility, but also the health of the baby. Plus, it can help prevent those pregnancy calf cramps. If you've had them then you know what I'm talking about.
  9. Selenium deficiency is associated with increased risk of miscarriage. This may be tied to thyroid function.
  10. Iodine is necessary for making thyroid hormone.
  11. Iron is needed for baby’s development and your ability to build healthy blood cells, which deliver oxygen to you and baby.
  12. Calcium for healthy bones.
  13. Choline is important for spinal cord formation.
  14. Vitamin A as beta carotene for immune system function, skin health and eye development. Retinyl palmitate is considered a teratogen and should not be taken in high doses during pregnancy. This is why using a prenatal specifically over a standard multivitamin is best. According to Linus Pauling Institute, no birth defects have been observed in vitamin A doses below 3,000 μg RAE/day (10,000 IU/day).
  15. Multiple capsules to be taken in divided doses. There is a limit to how much you can absorb at once. For example, the body can not absorb more than 600 mg of calcium at a time. And even absorbing that much is a stretch. In my practice, I advise my patients to avoid one-a-day vitamins for this reason.

Keep reading because I'm sharing a whole lot more about what to look for in a prenatal, as well as the prenatal vitamin I recommend to my patients.

What is the meaning of prenatal and postnatal?

Prenatal vitamins get their name because they are intended to be used before and during pregnancy. Prenatal refers to the time before and during pregnancy, but before birth. Postnatal (or postpartum) is the time following the birth of your baby. 

Your nutrient needs are higher while pregnant, but did you know they are even higher while breastfeeding? Not to mention you are recovering your body postpartum. This is why it is recommended that women continue their prenatal for as long as they are breastfeeding.

And the demands of postpartum are also why you need to build your nutrient stores before pregnancy. You see, if you enter into pregnancy nutrient depleted then you are going to have a difficult time building sufficient nutrient stores. You’ll be at a disadvantage.

I really want to stress the importance of looking after your prenatal health and engaging in preconception care. Getting “baby body ready” as we call it in my clinic is incredibly important for your health and your future baby’s. Growing a human is kind of a big deal, and it requires nutrients, energy, balanced hormones, and a healthy gut

As I talk about in the fertility chapter in Beyond the Pill, 6 months is really the minimum amount of time you should invest in preconception care. One to two years is even better. 

Sometimes women are shocked to hear this or they are impatient and want a baby now. I get that. And at the same time, it is important to recognize that you’ll be growing a baby just shy of a year, recovering postpartum (that’s a year process) and breastfeeding for 6 months to possibly 3 years or more. In that context, spending 6-12 months for a potentially 2-5 year endeavor isn’t too much of a stretch.

If you are on medication that depletes nutrients like the hormonal birth control pill, you must rebuild your nutrient stores before trying to conceive. Statins, which are known to deplete CoQ10, and Metformin that depletes B12 are other examples of medications that require you to replenish lost nutrients to prevent deficiency.

Increasing nutrient stores, balancing hormones, optimizing gut function, and improving thyroid health are all important steps to take before getting pregnant, to help you have a happy, healthy pregnancy. 

I share an entire fertility protocol in my book, Beyond the Pill.

What are prenatal vitamins?

While prenatal vitamins have very similar ingredients as a women's multivitamin, there are a few key differences. For example, iron and folate are in higher quantities in prenatal vitamins, because these are two key nutrients in the development of a fetus and mom’s health. It is well recognized that higher amounts of these nutrients are needed during pregnancy.

A prenatal vitamin taken in advance of pregnancy helps to build up nutrient stores to facilitate a healthy pregnancy and the creation of a healthy baby. It is a complement to a healthy, whole-foods diet. Even if we eat a balanced diet rich in nutrients, deficiencies are still very common (especially if we are on nutrient-depleting medication). That being said, eating a nutrient-dense diet is extremely important as a foundation because it provides more than just nutrients, like fiber, phytochemicals, and communicates to your body that the environment is plentiful and safe. A prenatal vitamin is definitely not a replacement for eating high quality foods. It is a compliment to your diet. 

I've got a resource for you to help get your diet in check to bump nutrients, balance hormones, & make this whole fertility journey much easier. Get a free recipe guide & meal plan 🙌 to get you started on your journey!

Do I really need prenatal vitamins?

A good prenatal can go a long way in helping you build your nutrient stores before baby. Yes, we want to load up on the good stuff way BEFORE we get pregnant. In fact, we need to do this at minimum 3 months before baby (that's how long your egg takes to mature, but girl 6-24 months is more ideal). And you want to focus on your diet too! 

You're going to need a prenatal – that's the real talks. Our food isn't as nutrient dense as it once was and we go into pregnancy way more nutrient depleted than ever before. That said, diet is the foundation and the supplement is just that, a supplement to your diet. More on diet soon!

With that in mind, you can easily see why a prenatal vitamin is so essential if you are pregnant, or want to become pregnant. 

What are the best prenatal vitamins for me?

Finding a good quality prenatal vitamin can be confusing and may contain things that you just plain don’t want to take in a vitamin—food dyes, hydrogenated fats, sugar, etc. That’s why I created Prenatal Plus, a complete formulation with active B vitamins, minerals, and antioxidants. Prenatal Plus supports your body while you try to become pregnant, during your entire pregnancy, and while you nurse. 

This formulation was also designed to provide comprehensive thyroid support with an ideal balance of iodine and selenium. Insufficient thyroid hormone leads to an increased risk of infertility and miscarriage. And the answer is almost never to just take more iodine.

Prenatal Plus provides amazing support for nutrient depletions caused by hormonal birth control as well. 

Learn more about Prenatal Plus here!

Finding the best prenatal can feel confusing. There is so much out there on the market that is not regulated, not quality, and isn’t delivering the best nutrition. I sometimes also see well intentioned people telling women that they can take vitamins that contain harmful nutrients and herbs as if pregnancy isn’t a consideration in supplement selection. A developing baby is susceptible to many things in your environment, so I would encourage you to use caution when selecting supplements. 

Talking with a qualified physician who is trained in nutrition and supplement use can help you navigate this tricky decision. Please note that if you meet with a doc who dismisses supplements or tells you they are all the same, you should question how much training they’ve had on the topic. Your doctor may be very smart with what they know and may be incorrectly commenting on a topic they are not educated in. They aren’t a bad person for this, but at the same time, they are also not qualified.

Let’s chat about what the best prenatal vitamins contain.

A good prenatal vitamin should contain:

  1. Vitamin A as beta carotene and retinyl palmitate combined daily to support immune function, fetal growth, gene transcription, and lung development. Vitamin A deficiencies are associated with increased risk of infection, night blindness and maternal death. Vitamin A deficiency can also make iron deficiency worse. It has previously been recommended to supplement with beta carotene only, which is the precursor to vitamin A. However, in light of new research showing genetic mutations in BCMO1 can decrease the ability to convert beta-carotene into active vitamin A, it is now considered important to have a low dose of retinyl palmitate as a source of vitamin A in a prenatal. Pre-formed vitamin A or retinyl palmitate should not exceed 10,000 IU or 3,000 mcg RAE/day. Aim for 770-1,300 mcg RAE/ day of mixed betacarotene and retinyl plamitate.
  2. Vitamin C 200-2,000 mg to aid in tissue formation, including collagen, protection from free radicals, and neurotransmitter synthesis. Generally, an additional vitamin C supplement is needed outside of a prenatal vitamin to achieve levels of 500 mg or more.
  3. Vitamin D 1,000 mg to support immune function, bone formation, and healthy fetal development. Insufficient vitamin D has been associated with increased risk of preeclampsia, bacterial vaginosis and gestational diabetes. Testing your vitamin D is the best way to know the more appropriate dose for you. 
  4. Vitamin E 40-400 IU daily for free radical protection and healthy cells. 
  5. Vitamin K1 100 mcg for appropriate blood clotting.
  6. Folate 800 mcg (like methylfolate not the synthetic folic acid) to support dividing cells
  7. B12 10-20 mcg of methylcobalamin. Certain medical conditions may require more. The RDA is currently 2.6 mcg in pregnancy.
  8. Iron 27 mg. Avoid sulfate forms which can cause digestive upset, constipation and isn’t well absorbed. Look for iron bisgylcinate because it is the most bioavailable form of iron, it’s non-constipating, and usually causes no other gastrointestinal upset.
  9. Choline 40-100 mg for brain and nervous system development. Choline, folate and B12 are important in preventing neural tube defects.
  10. Calcium 300-600 mg for the formation of healthy bones. As much as 350 mg per day are transferred to the baby in the third trimester.
  11. Magnesium 100-300 mg. You may need an additional magnesium supplement in addition to a prenatal.
  12. Selenium 200 mcg to provide antioxidant protection and support thyroid health
  13. Chelated zinc 10-15 mg to help reduce the risk of a preterm baby
  14. Iodine 150-290 mcg, because deficiency in infancy can lead to learning disabilities
  15. Biotin is a crucial nutrient in pregnancy. In fact, biotin deficiency has been shown to be teratogenic (causes birth defects) in many species.

Avoid Prenatal Vitamins With:

  1. Food dye or food coloring
  2. Hydrogenated fats
  3. Folic acid (choose folate instead)
  4. Retinyl palmitate of 10,000 IU or more
  5. Iodine without selenium
  6. MSG
  7. Polyethylene glycol 

Your prenatal should also have the GMP (good manufacturing practices) on the label, which ensures the highest quality manufacturing to create a consistent and quality vitamin.

If you're looking for a prenatal designed by a woman for women then check the Prenatal Plus I recommend to patients.

If you're even thinking about having a baby in the next couple of years, do your body and baby a favor and start a quality prenatal now!

My Prenatal Plus formulation has all these crucial nutrients and more (like full spectrum B vitamins). 

When to start taking prenatal vitamins

Most women start taking prenatals right before they want to start trying for a baby. I advise a different approach. The egg you become pregnant is maturing 3 months prior to ovulation. That means whatever you were or weren’t doing 3 months prior to conception impacted that egg.

Since prenatals are loaded with nutrients to support you and the growth of a fetus, they can be very useful for some women who are not trying to conceive, especially if they are on the Pill (which depletes nutrients like you wouldn’t believe). 

And if you envision a baby in your future, I recommend starting at least prenatal six months before you begin trying to get pregnant. 

Why is six my magic number? The egg you ovulate and become pregnant with matures over a three-month span. At certain times during its maturation, your eggs are really vulnerable to environmental toxins and other dangers to their health. This is when minerals and B vitamins become so important: they protect the health of your eggs. 

By starting prenatals six months before you try to conceive, you are supporting healthier egg development and helping your body replenish any important nutrients that may be low or deficient.

How long should I take prenatal vitamins for?

You should start prenatal vitamins six to twenty-four months before you want to start baby-making, to give your body the support it needs to prepare for pregnancy. Your prenatal vitamin should then also be taken for the duration of your pregnancy and for as long as you’re breastfeeding. 

If you’re looking for more postpartum support, check out my first book, Healing Your Body Naturally After Childbirth.

Other prenatal health advice

The Best Foods During Pregnancy

I am a huge advocate for eating loads of vegetables on a daily basis. They contain vitamins, minerals, and fiber—all so important for pregnancy. Aim for six to nine servings of veggies a day. Sound impossible? Start small. Add one serving of vegetables to your diet daily for a week. The next week, add an additional serving, until you hit six to nine daily servings of veg. 

Fruits (like berries) are vitamin powerhouses with the added benefit of containing antioxidants, which reduce inflammation in the body. 

Protein is hugely important during pregnancy, and meat, poultry, and beans are great sources. They also contain B vitamins and iron, both necessary to support a healthy pregnancy.

Eat leafy greens, high quality proteins, seafood, kelp, organ meats (yeah I went there), and other nutrient dense foods to help support your overall health. Feeling lost about food? Grab my hormone balancing nutrient dense meal plan!

These foods contain nutrients that are also found in prenatal vitamins. 

  1. Avocados supply you with vitamin A, B6, and magnesium.
  2. Eggs are rich in choline, vitamin A, biotin and are a complete protein.
  3. Salmon that is wild caught can provide you with a healthy does of both selenium and iodine.
  4. Cabbage is a source of B6, vitamin C, and copper.
  5. Spinach contains folate, calcium, magnesium, and an antioxidant called alpha-lipoic acid.
  6. Organic, grass-fed red meat is an ample source of bioavailable iron. That means you can absorb it much easier, especially compared to plant based iron.
  7. Lentils contain folate, selenium, magnesium, iron (not highly bioavailable), B1, B2, copper and zinc.
  8. Tomatoes contain antioxidants, folate, and vitamin C.
  9. Swiss Chard is a great source of folate.
  10. Red Bell Pepper is rich in vitamin C, vitamin A, and B6.

Prenatal Yoga

Yoga has long been popular for its benefits for both body and mind. However, prenatal yoga (yoga especially for pregnant women) holds an added bonus: It may help with labor!

Prenatal yoga can also help with lower back pain, headaches, sleep quality, and body strength. 

Remember, though, that we are all different. In some instances, prenatal yoga may not be safe. There are also forms of yoga (e.g. bikram) that should be avoided during pregnancy. Always ask your physician before starting any exercise program. 

Check out the resources on Yoga Journal for prenatal yoga support.

Rethink the Pill 

I never want women to feel ashamed for taking the Pill. That is not my intention. I merely want you to have all the information, so you are able to make informed decisions about your body and your health. 

That being said, if you are on the Pill and are thinking about getting pregnant soon, I recommend you ditch it. The Pill depletes nutrients (many of which are so important for fertility), causes inflammation, and can send your thyroid into a tailspin—none of which are optimal conditions for a healthy pregnancy. 

Starting the 30-Day Brighten Program six months to a year before conception can help your body start to regain balance if the Pill has caused mayhem.

Full Thyroid Panel

If your thyroid is struggling in anyway prior to getting pregnant then odds are, it is only going to get worse. You see, pregnancy is a stress test for your thyroid and if your thyroid was already struggling…well, it aint gonna get better in pregnancy.⁠

In fact, new onset of hypothyroidism is common in pregnancy.⁠

What is hypothyroidism? It is a state in which you do not create sufficient thyroid hormone.⁠

Every cell in your body has a receptor for thyroid hormone. This means every cell needs it to function.⁠

For mom, that dip in free T3 specifically causes fatigue, pronounced weight gain, depression, anxiety, dry skin, constipation, and more.⁠

But for baby, it's the lack of free T4 that is the problem. This is what crosses the placenta and fuels baby's development in the first trimester.⁠⁠

How to know if you're at risk? Get a complete thyroid panel!⁠

If you have a TSH >2.5 then repeat testing and discussion of a thyroid medication needs to happen if you're actively trying to conceive.⁠

If you are hypothyroid, you need to be monitored throughout your pregnancy. In my practice, I give every woman trying to become pregnant a lab order to test her thyroid as soon as she has a positive pregnancy test. Yes, hypothyroidism can hit that quick.⁠⠀

A full prenatal thyroid panel includes:

  1. TSH
  2. Total T4
  3. Total T3
  4. Free T4
  5. Free T3
  6. Reverse T3
  7. Anti-TPO
  8. Anti-thyroglobulin
In this video I review what you should know about your thyroid health and your fertility!


Low progesterone can make becoming and remaining pregnant difficult and can put you at increased risk of miscarriage. If you struggle with PMS symptoms (like mood swings, anxiety, and disturbed sleep), I recommend having your progesterone levels tested, because those symptoms could indicate low progesterone. 

Work with a licensed medical provider to understand if progesterone therapy is right for you.

Watch this video to understand the signs and symptoms of low progesterone and what you can do to increase progesterone naturally.


Medical Definition Of Teratogen – MedicineNet

Diet during Pregnancy – American Pregnancy Association

Prenatal yoga – American Pregnancy Association

Pregnancy week by week – Mayo Clinic

Curtis K, Weinrib A, Katz J. Systematic Review of Yoga for Pregnant Women: Current Status and Future Directions. Evidence-Based Complementary and Alternative Medicine. 2012;2012:1-13. doi:10.1155/2012/715942

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About The Author

Dr. Jolene Brighten

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Dr. Jolene Brighten, NMD, is a women’s hormone expert and prominent leader in women’s medicine. As a licensed naturopathic physician who is board certified in naturopathic endocrinology, she takes an integrative approach in her clinical practice. A fierce patient advocate and completely dedicated to uncovering the root cause of hormonal imbalances, Dr. Brighten empowers women worldwide to take control of their health and their hormones. She is the best selling author of Beyond the Pill and Healing Your Body Naturally After Childbirth. Dr. Brighten is an international speaker, clinical educator, medical advisor within the tech community, and considered a leading authority on women’s health. She is a member of the MindBodyGreen Collective and a faculty member for the American Academy of Anti Aging Medicine. Her work has been featured in the New York Post, Forbes, Cosmopolitan, Huffington Post, Bustle, The Guardian, Sports Illustrated, Elle, and ABC News. Read more about me here.