Study shows 90% of pregnant women have micronutrient deficiencies

Before and during pregnancy, consuming the right mix of micronutrients, or vitamins and minerals, can impact a growing baby’s growth and development. And having low levels of certain nutrients during pregnancy can increase the risk of a wide range of pregnancy complications, including anemia, gestational diabetes, hypertension, and preeclampsia. 

Past data has shown that women who live in low and middle-income countries are at risk of not consuming enough micronutrients during and before pregnancy. But according to a new study published in PLOS Medicine, almost 90% of pregnant women who live in wealthier countries aren’t eating enough of certain micronutrients, too—and those who eat a more plant-based diet may have even greater nutritional gaps. 

However, with this concerning news comes a solution—supplementation may help bridge the gap. 

Study finds more micronutrients are needed to fill nutrient gaps in pregnancy 

In the past, researchers couldn’t confirm the exact influence vitamin supplementation has on vitamin status during pregnancy. To address this knowledge gap, researchers aimed to find patterns of vitamin status during each stage of the reproductive cycle to see what influence supplementation truly has. 

To do this, researchers evaluated 1,729 women from the United Kingdom, Singapore, and New Zealand (all countries that are considered to be high-income) between the ages of 18 and 38 years. All of these women were planning to try to conceive. 

The multicenter, double-blind, randomized controlled trial was designed so that each participant was randomized to receive either a standard vitamin supplement or an enhanced vitamin supplement starting in preconception and continuing throughout pregnancy. Both options included folic acid, beta-carotene, iron, calcium, and iodine. The enhanced vitamin contained additional nutrients—riboflavin, vitamins B6, B12, and D, myo-inositol, probiotics, and zinc. The levels found in these supplements were comparable to what is typically found in an over-the-counter supplement. 

Results found that, even though the women lived in countries where access to nutritious food isn’t as much of a concern when compared with lower and middle-income countries, over 90% of the trial participants had marginal or low concentrations of one or more of folate, riboflavin, vitamin B12, or vitamin D during preconception before they started taking the supplements. In those who didn’t get the supplement with the additional nutrients, their plasma concentrations showed markers of B6 and B12 insufficiency during pregnancy.

“People think that nutrient deficiency only affects people in underdeveloped countries—but it is also affecting the majority of women living in high-income nations,” author and Professor of Epidemiology Keith Godfrey, from the University of Southampton, shared. 

He also speculated that “The push to reduce our dependence on meat and dairy to achieve net-zero carbon emissions is likely to further deplete expecting mothers of vital nutrients, which could have lasting effects on unborn children.” Meat and dairy are sources of vitamin B12, a nutrient that was found to be a concern in this study. 

The authors noted that taking a supplement with a wider variety of micronutrients during preconception and pregnancy reduced the prevalence of vitamin deficiency and depletion markers before and during pregnancy.

Nutrition supplementation during pregnancy

According to a survey conducted by the March of Dimes, only 34% of surveyed women reported taking prenatal vitamins before they knew they were pregnant. And data shows that only 55% to 60% of pregnant women report taking one in the first trimester, with that percentage increasing as pregnancies progress. Not all OB-GYNs proactively recommend taking a prenatal vitamin, according to data published in 2023 in the Archives of Gynecology and Obstetrics. In fact, per this study, only 26% of physicians surveyed tell women who are trying to conceive to take certain important supplements, like DHA. And only 56% to 67% of gynecologists recommended vitamin D supplementation before and during pregnancy.

While people may assume that just because they eat their fruits and veggies every day they are meeting their nutrition needs, this current data suggests otherwise. 

Part of this may be because the intake requirements of many micronutrients increase during pregnancy. For example, it is recommended to take 400 mcg DFE of folic acid every day when you are not pregnant. But during pregnancy, the suggested intake increases to 600 mcg DFE. This increased value may be challenging to meet via a standard diet. 

Another reason may be due to some people eliminating entire food groups for health or environmental reasons. While doing so may support certain aspects of health, it may also increase the risk of nutritional gaps. 

This new data shows, for the first time, that an enormous proportion of women who are trying to conceive or are pregnant are deficient in micronutrients, a factor that may increase the risk of experiencing negative pregnancy outcomes if the deficiencies are not replenished. It also shows that the simple act of taking a prenatal multivitamin that contains a wide variety of nutrients can help reduce vitamin deficiencies during preconception and pregnancy. 

How to pick a prenatal vitamin

It is generally recommended to start taking a prenatal vitamin 3 months before you start trying to conceive. And while it may be a simple task to take a prenatal, finding the right one out of the sea of options can be daunting. 

Here are some criteria to consider with your healthcare provider when choosing a prenatal vitamin:

• At least 400 mcg of folic acid (or more, depending on your diet). Adequate intake of folic acid leads to a significantly reduced occurrence of spina bifida and congenital heart defects.
• At least 300 mg of DHA omega-3 fatty acid. There is evidence that preconception supplementation improves embryonal development and supports the growing baby’s eye and brain development. In randomized-controlled trials, the supplementation of fish oil or long-chain omega-3 fatty acids led to a significant reduction in the risk of premature birth up to 34 weeks of gestation.
• Between 150-220 mcg of iodine. Iodine deficiency is one of the most common reasons for manifest or latent hypothyroidism. Studies show that hypothyroidism in pregnant women is associated with delays in newborn development.
• Vitamin D. Adequate vitamin D is essential for a developing fetus’s bone mineralization. And several studies showed the association of low maternal vitamin D status with pregnancy complications such as preeclampsia, preterm birth, or low birth weight. Studies have also shown that 18–80% of pregnant women have deficient vitamin D levels. Ideally, you would get a baseline vitamin D level checked to know how much supplementation is indicated. 

Other nutrients that women may benefit from having in their prenatal vitamins include iron, vitamin B12, choline, calcium, and magnesium, but this list is not exhaustive. 

Your prenatal vitamin should also be third-party verified to ensure what the label claims is accurate and tested for heavy metals. Ultimately, you should choose a prenatal vitamin with your healthcare provider to ensure you are picking the best one for your unique needs. But if you are going to take anything away from this study, it’s that unless you are eating a diet that is incredibly high-quality every single day, a prenatal vitamin is an important addition to your preconception and pregnancy diet.

Sources

These are our favorite prenatal vitamins to recommend

Perelel

1. 1st Trimester Prenatal Vitamin Pack

•

$48

Perelel’s ingenuity lies in the fact that it offers a different vitamin formulation for each trimester and beyond—this is brilliant, because each trimester comes with its own needs. Perelel’s core prenatal is OB-GYN formulated and divided into two doses, with additional separate supplement add-ons for each stage, like ginger and B6 in the first, calcium and magnesium in the second plus a probiotic in the third. They also offer complimentary recycling for pill sachets.

SHOP

Needed

2. Prenatal Multi Powder

•

$69.99

For mamas with pill fatigue or morning sickness, Needed’s prenatal vitamin powder can make getting your nutrients much easier to stomach. Needed also offers a capsule formulation and an optional iron add-on, so if supplementing iron isn’t for you, you can opt to omit. The powdered formula also means you’ll get 550 mg of choline (unheard of in a prenatal!)—in a fully edible form. Just whip up your favorite smoothie and add it in. 

SHOP

Ritual

3. Essential Prenatal

•

$39

I like Ritual’s “everything you need; nothing you don’t” philosophy, which is a good mentality for pregnancy and baby gear in general. Their prenatal contains just the essentials with just 12 nutrients packed into a delayed-release capsule to promote good absorption. I love that it contains methylated B vitamins, bioavailable iron and 350 mg of DHA, an omega-3 fatty acid that’s necessary for fetal brain and eye development.

Read more about it here.

– Jessica D’Argenio Waller, MS, CNS, LDN, Motherly’s Editorial Director

SHOP

Innate Response

4. Baby & Me Prenatal

•

$39.96

The Baby & Me prenatal from Innate Response contains food forms of several nutrients and comes in a divided dose. It’s naturopath-formulated and I’ve found it’s easier on the stomach than other prenatal tablets—but still packs major nutritional value.

– Jessica D’Argenio Waller, MS, CNS, LDN, Motherly’s Editorial Director

SHOP

Bird & Be

5. The Gentle Prenatal

•

$36

Bird & Be’s gentle prenatal is easier on nauseated mamas than other supplements, as it contains just the basics—ideal if you have trouble keeping heavier-duty blends down. I especially appreciate that they include extra B6, which has been shown to help reduce morning sickness, and a whopping 300 mg of choline. (Price is for a 30-day supply.)

– Jessica D’Argenio Waller, MS, CNS, LDN, Motherly’s Editorial Director

SHOP

Care/of

6. Prenatal

•

$18.99 for 30 days

Care/of’s prenatal blend contains 22 nutrients designed to support both mom and baby during pregnancy, with methylated B vitamins and easily absorbed iron (my preferred form for those nutrients). Thankfully, this high quality doesn’t mean a high price tag: It’s one of the more affordable options on the list, at just $18.99 for a 30-day supply.

SHOP

Tend Prenatal

7. Lemon Berry

•

$99 for a 28-pack monthly subscription

The Tend Prenatal comprises 27 essential nutrients and an equivalent of 8 servings of fruits and vegetables, all wrapped up in a convenient bar form that’s ideal for on-the-go or to be stashed in your nightstand for when nausea strikes. The best part? You don’t have to take it with food, because it is food. The bars are filled with fiber and plant-based fats, which mean they’re satisfying to boot. 

“You turn to the ingredients list and it begins with organic cashew butter and ends with non-gmo microalgae oil. Most nutrient dense bar. No filler. It’s all about the quality and Tend gets it,” says reviewer MJ M.

SHOP

Mary Ruth Organics

8. Prenatal & Postnatal Liquid Multivitamin

•

$44.95

Just two tablespoons of this berry-flavored blend will get you a potent serving of 20 different nutrients, plus ginger root extract, a slew of trace minerals and hesperidin, a citrus-based bioflavanoid that’s helpful for fighting inflammation. Stir your serving into smoothies or sip it with breakfast. Note that this formula doesn’t contain iron, which may be helpful in pregnancy and postpartum, so talk to your birth provider about adding in an extra liquid iron supplement, too.   

SHOP