Prenatal vitamins are formulated so that pregnant women can obtain all the micronutrients they require to keep their body growing, fuel hormonal changes, and support the baby growing in your belly (1).
Not to mention, they help deal with the hormonal changes occurring during pregnancy that can lead to anemia, morning sickness, and other unpleasant side effects (2).
The best time to take them is before you conceive. This is because the baby’s brain and spinal cord are developed in the first month – which makes it imperative to have adequate nutrients for both you and the baby.
Folic acid is vital for healthy baby growth. Folate actually comes in two forms. The naturally occurring folate and the synthetic folic acid. While synthetic, folic acid is more stable than folate and absorbed 1.67 times as well (3).
Folate is essential for cell growth and working with B12 to make red blood cells. Red blood cells that deliver oxygen to you and your baby, making this necessary for both of your lives.
Most notably, a 2013 study published in the Journal of the American Medical Association demonstrated that folate prevents neural tube defects, such as anencephaly and spina bifida, by 50-70% (4).
Another 2011 study also showed that folic acid reduces autism spectrum disorders developing in children (5).
Vitamin B12 is important for fetus development. A 2000 study showed that having a B12 deficiency and lead to anemia – making you feel tired, slow, and lousy (6).
The study also demonstrated that those with B12 deficiency doubled their risk for developing depression.
Another 1963 study, which still holds true today, shows that B12 is needed for nervous system development and red blood cell formation – making it essential for pregnant women (7).
Iron is your key for energy. During pregnancy, a woman increases her blood volume as a result of the growing fetus. Pregnant women, on average, need 50% more iron than non-pregnant women (8).
Without enough iron in your diet, you can become anemic because your body prioritizes your growing baby’s oxygen demands.
Even if you eat iron, it may not be enough because approximately 40% of the iron in meat is heme (easily absorbed) iron. That means 60% of it is nonheme (not easily absorbed) (9).
Lastly, supplementing with iron has been shown to cut the risk of preterm delivery.
Calcium is the key for hormone signaling cascades and a healthy skeleton. A study done in 1996 shows that calcium plays a hand in bone growth, cell signaling, muscle contractions, and even blood clotting- just to name the main functions (10).
Mono-ortho-calcium phosphate keeps your body alkaline. When you metabolize the food you eat, and it increases the acidity in your body, you end up having to make more mono-ortho-calcium phosphate blood levels in the proper range (11).
The issue for pregnant women is that this calcium often comes from your bones (12). A prenatal vitamin can prevent the calcium bone leaching.
A 2005 study published in the American Journal of Clinical Nutrition showed that following a diet high in fruits and vegetables while shifting to eating fewer meats or dairy products will reduce the acidic load on your kidneys (13).
You may need zinc and copper too for optimal health. A 1986 study showed that as iron supplementation increases (pregnant women need approximately 50% more), zinc and copper absorption seems to be negatively affected (14).
It becomes extremely important then to increase your intake of copper and zinc to counteract this.
Boost your fiber intake to avoid excessive pregnancy weight gain. A study published in the American Journal of Clinical Nutrition showed that high fiber foods slow down digestion, which can help avoid excess pregnancy weight gain (15).
The more time it takes to break down your food, the less of a rise you will have in your blood sugar and the longer you will feel full after eating (16).
A higher fiber dramatically increases the chance of having a baby with a healthy weight. A 2002 study showed that adequate fiber intake by mothers during pregnancy is seen to increase the odds of your baby being born a healthy weight 4-5 fold compared to those who rarely eat fiber (17).
Fiber feeds your “good” gut bacteria. A 2013 study showed that fiber nourishes your gut’s healthy bacteria. This bacteria can actually break down the fiber you eat and turn it into by-products that improve your weight and help prevent chronic disease (18).
Probiotics supercharge the microbiome. A study published in Nutrients showed the probiotics can provide and increase the absorption of vitamin K, vitamin B12, protein, and nutrients that fight cancer or reduce inflammation (19).
There are probiotic supplements you can purchase, but by eating more fiber-filled foods, you’ll naturally feed and grow the bacteria in your gut. For certain situations, like after taking antibiotics or with a history of dysbiosis (frequent yeast infections), it may make sense for you to call in the troops and invest in a probiotic supplement.
Essential fatty acids build healthy brains and nervous systems. Essential fatty acids are not produced by the body, meaning it’s essential to eat them in our daily diet (22).
Unfortunately, most prenatal vitamins do not include these essential fatty acids. This is problematic because studies show that the two long-form essential fatty acids, DHA and EPA, are needed to build up your baby’s brains, eyes, and nervous system (23, 24).
A 2005 study showed that consuming fish that have natural levels of these essential fatty acids may increase your consumption of contaminants such as BPA or heavy metals (25).
Supplement with ginger to alleviate morning sickness. A 1992 study published in the Journal of Clinical Endocrinology and Metabolism showed that the hormonal changes from estrogen and human chorionic gonadotropic hormone during pregnancy lead to vomiting and nausea (26).
A 2009 study showed that about 80% of pregnant women experience nausea during the day mostly between the 6th and 12th week of pregnancy (27).
In extreme cases, you may actually have hyperemesis gravidarum, a rare diagnosis where you have vomiting to the extent of weight loss and electrolyte balance (28).
Increasing the amount of ginger you consume, found in prenatal supplements, is seen to reduce morning sickness anecdotally.
According to a 2014 review which analyzed 12 studies, supplementing with 1.1-1.5 grams of ginger can significantly reduce symptoms of nausea (29).
Vitamin D is necessary during the 3rd trimester for healthy bones development. A 2006 study showed that while Vitamin D plays many roles in pregnancy, it is best known for assisting to direct and build a healthy skeleton, especially in the third trimester for (30).
If you lack vitamin D during pregnancy, your baby may be deficient at birth. This can put your child at risk for abnormal bone growth, delayed physical development and rickets (which can lead to fractures and deformity (31).
A 2011 study showed that deficiency of vitamin D has also been linked to a greater risk of developing pregnancy complications such as preeclampsia and gestational diabetes (32).
Vitamin A is toxic in high amounts, especially for pregnant women. Vitamin A is fat soluble. This means when vitamin A is consumed in large doses it is not easily flushed out of the body, like water-soluble vitamin C. Instead vitamin A is stored in fat cells (33).
With too much vitamin A you end up with changes and damage to DNA (34).
Prenatal vitamins can cause nausea. Certain vitamins can cause nausea when taken on an empty stomach. Taking them with food is always a better option.
Prenatal vitamins can cause constipation. Excess iron can lead to constipation. You can counter this by increasing the amount of dietary fiber you consume.
Prenatal vitamins can change urine color or odor. B vitamins, in particular, may be the contributing factor, though these are harmless changes.
A small dose of B12 will last you for years. Only 2.4 micrograms daily will ensure you have enough vitamin B12 that the liver can store for years (35).
An ideal prenatal supplement only needs calcium, vitamin D, iron, and folic acid. You don’t have to take 11 or more distinct pills to ensure your best pregnancy ever. In fact, keeping track and buying all those pills would be a waste of your time and money.
Instead, you just need 4: vitamin D, calcium, iron, and folic acid.
Calcium, iron, and folic acid are the three essential vitamins 99% of all women need for their pregnancy, and vitamin D will support proper calcium metabolism (36).
Next, many prenatal vitamins lack the essential fatty acids you need for optimal brain and nervous system formation in your growing baby, so a quality omega 3 fatty acid supplement containing EFA and DHA is number two here (37).
Lastly, probiotics because during pregnancy you are likely to suffer from constipation and increased risk of infection. Having probiotics in your system helps to strengthen your immune system and supports regular bowel movements (38).
You can start taking a prenatal vitamin as early as 3 months before conception. The time for critical growth of your baby is a few weeks right after conception as you go from the 1st to the 2nd trimester (39).
Note that at any point during your pregnancy is it not too late to begin improving your nutrition and consuming prenatal vitamins.
Even after you have your baby, it is still ideal to continue taking your prenatal supplements to support healthy breastfeeding, which can burn hundreds of calories a day and drain you of as many nutrients as your third trimester (40).
With extra iron consumption, it’s recommended to have 15 mg of zinc and 2 mg of copper (41).
Q: Is it ok to take prenatal vitamins if you’re not pregnant?
A: You may be tempted to take prenatal vitamins because of unproven claims that they promote thicker hair and stronger nails. However, if you’re not pregnant and not planning to become pregnant, high levels of certain nutrients over an extended period of time may actually be more harmful than helpful.
Q: Do prenatal vitamins make you more fertile?
A: Taking a prenatal vitamin alone probably won’t significantly increase your chances of getting pregnant, though it can help.
Q: Are prenatal vitamins really necessary?
A: Yes, most women can benefit from taking a prenatal vitamin and mineral supplement (preferably before trying to conceive). Think of it as an insurance policy to make sure you’re getting the right amount of certain crucial nutrients during pregnancy.
Q: Why do I feel sick after taking prenatal vitamins?
A: Without food to keep them busy, your stomach acids start to chew on you, a process that, not surprisingly, produces nausea.
Q: Can you have a miscarriage from not taking prenatal vitamins?
A: Prenatal vitamins are usually recommended during a woman’s pregnancy to prevent congenital disabilities. The evidence on prenatal vitamins and decreased miscarriage risk has been mixed.
Q: Do prenatal vitamins make you gain weight if you are not pregnant?
A: No vitamin, neither a regular multivitamin nor a prenatal, can make you gain weight. This is because vitamins do not contain any calories, and you can’t break them down for energy or store them as fat.
Q: Do prenatal vitamins mess with your hormones?
A: No, prenatal vitamins do not mess with your hormones.
Q: Do prenatal vitamins make you poop a lot?
A: Pregnant women need 27 milligrams of iron daily, and many prenatal vitamins contain 30 milligrams. The most common side effect of iron is constipation, but it can also cause diarrhea in some cases. It’s normal if your stools look a bit darker when you start taking a prenatal vitamin but you will not necessarily poop more.
Q: Do prenatal vitamins mess up your period?
A: There’s no truth to the claim that prenatal vitamins can help regulate your period. Your period depends on hormones released by various body organs, not on vitamins you take.
Q: Do prenatal vitamins make your hair grow faster?
A: No, there is little scientific evidence to support taking prenatal vitamins as hair vitamins. The myth of their benefits arose because women who usually take prenatal vitamins – that is, pregnant women – naturally have long, thick, fast-growing hair due to pregnancy hormones.
Being pregnant places a significant strain on your body, which makes sense because you’re supporting yourself AND your growing baby. It’s essential to work with your OBGYN to determine the best supplements to support your health, your sanity, and your energy.
At the very least it is safe and necessary to include a basic prenatal vitamin, an essential fatty acid supplement, and a probiotic.
This ensures your bases are covered and that you and your baby can thrive during the 9 months of baby development.