If you’re pregnant, you may think that feeling overwhelmed and confused comes with the territory. But it doesn’t have to be so confusing regarding vitamins and supplements.
If you did your extra credit work, we bet you already know that high mercury seafood, alcohol, and cigarettes are off-limits during pregnancy. What may surprise you is that some vitamins, minerals, and herbal supplements should also be avoided.
Information on which supplements are safe and which aren’t can vary and can make things feel even more complicated. We’ve got you, though.
This article breaks down which supplements are believed to be safe to take during pregnancy and why some supplements should be avoided.
Why take supplements during pregnancy?
Getting the right nutrients is important at every stage of life, but it’s especially critical during pregnancy, as you’ll need to nourish yourself and your growing babe.
Pregnancy increases the need for nutrients
During pregnancy, macronutrient intake needs to grow significantly. Macronutrients include carbohydrates, proteins, and fats.
For example, protein intake needs to increase from the recommended 0.36 grams per pound (0.8 grams per kg) of body weight for non-pregnant women to 0.5 grams per pound (1.1 grams per kg).
You’ll want to include protein in every meal and snack to meet your needs.
The requirement for micronutrients, which include vitamins, minerals, and trace elements, increases even more than the need for macronutrients.
While some people can meet this growing demand through a well-planned, nutrient-dense eating plan, it can be challenging for others.
You may need to take vitamin and mineral supplements for various reasons, including:
- Nutrient deficiencies: Some people may need a supplement after a blood test reveals a deficiency in a vitamin or mineral. Correcting deficiencies is critical, as a shortage of nutrients like folate has been linked to birth defects.
- Hyperemesis gravidarum: This pregnancy complication is characterized by severe nausea and vomiting. It can lead to weight loss and nutrient deficiencies.
- Dietary restrictions: Women who follow specific diets, including vegans and those with food intolerances and allergies, may need to supplement with vitamins and minerals to prevent micronutrient deficiencies
- Smoking: Although it’s critical for mothers to avoid cigarettes during pregnancy, those who continue to smoke have an increased need for specific nutrients like vitamin C and folate.
- Multiple pregnancies: Women carrying more than one baby have higher micronutrient needs than women carrying one baby. Supplementing is often necessary to ensure optimal nutrition for the mother and her babies.
- Genetic mutations like MTHFR: Methylenetetrahydrofolate reductase (MTHFR) is a gene that converts folate into a form the body can use. Pregnant women with this gene mutation may need to supplement with a specific form of folate to avoid complications.
- Poor nutrition: Women who undereat or choose foods that are low in nutrients may need to supplement with vitamins and minerals to avoid deficiencies.
In addition, experts like those at the American College of Obstetricians and Gynecologists (ACOG) recommend that all pregnant people take a prenatal vitamin and folic acid supplement. This is advised to fill nutritional gaps and prevent developmental abnormalities at birth like spina bifida.
Depending on your circumstances, be prepared to take on the task of adding supplements to your daily routine if directed by your healthcare provider.
Herbal supplements can help with ailments — with caution
In addition to micronutrients, herbal supplements are popular.
One 2019 study found that 15.4 percent of pregnant women in the United States use herbal supplements. However, not all disclose to their physicians they’re taking them. (A 2017 study found about 25 percent of herbal supplement users in the United States don’t tell their docs.)
While some herbal supplements may be safe to take during pregnancy, there are far more that might not be.
Although some herbs can help with common pregnancy ailments like nausea and upset stomach, some may harm you and your baby.
Unfortunately, there isn’t much research regarding pregnant people’s use of herbal supplements, and much is unknown about how the supplements can affect you.
The safest bet? Keep your doctor informed about any changes to your eating plan and supplements.
Supplements considered safe during pregnancy
Just as with medications, your doctor should approve and supervise all micronutrient and herbal supplements to ensure they’re necessary and taken safely.
Always purchase vitamins from a reputable brand with its products evaluated by third-party organizations like the United States Pharmacopeia (USP).
This ensures that the vitamins adhere to specific standards and are generally safe to take. Not sure which brands are reputable? Your local pharmacist can be a lot of help.
Suggested read: B-complex vitamins: Benefits, side effects and dosage
1. Prenatal vitamins
Prenatal vitamins are multivitamins specially formulated to meet the increased demand for micronutrients during pregnancy.
They’re intended to be taken before conception and during pregnancy and breastfeeding.
Observational studies have shown that supplementing with prenatal vitamins reduces the risk of preterm birth and preeclampsia. Preeclampsia is a potentially dangerous complication characterized by high blood pressure and protein in the urine.
While prenatal vitamins aren’t meant to replace your healthy eating plan, they may help prevent nutritional gaps by providing extra micronutrients that are in high demand during pregnancy.
Since prenatal vitamins contain the vitamins and minerals you’ll need, taking additional vitamin or mineral supplements may not be necessary unless your doctor suggests.
Prenatal vitamins are often prescribed by doctors and are available over-the-counter.
Folate is a B vitamin that plays an integral role in DNA synthesis, red blood cell production, and fetal growth and development.
Folic acid is the synthetic form of folate found in many supplements. It gets converted into the active form of folate — L-methylfolate — in the body.
It’s recommended to take at least 600 micrograms (mcg) of folate or folic acid per day to reduce the risk of neural tube defects and congenital abnormalities like cleft palate and heart defects.
In a review of five randomized studies including 6,105 women, supplementing with folic acid daily was associated with a reduced risk of neural tube defects. No negative side effects were noted.
Although adequate folate can be obtained through diet, many women don’t eat enough folate-rich foods, making supplementation necessary.
Additionally, the Centers for Disease Control and Prevention (CDC) recommends that all women of childbearing age consume at least 400 mcg of folate or folic acid per day.
This is because many pregnancies are unplanned, and birth abnormalities due to a folate deficiency can occur very early, even before most women know they’re pregnant.
Suggested read: Vitamin B12 dosage: How much should you take per day?
It may be wise for pregnant women, especially those with an MTHFR genetic mutation, to choose a supplement that contains L-methylfolate to ensure maximum uptake.
The need for iron increases significantly during pregnancy as maternal blood volume increases by about 45 percent.
Iron is critical for oxygen transport and the healthy growth and development of your baby and the placenta.
In the United States, the prevalence of iron deficiency in pregnant women is around 18 percent, and 5 percent of these women have anemia.
Anemia during pregnancy has been associated with preterm delivery, maternal depression, and infant anemia.
The recommended intake of 27 milligrams (mg) of iron per day can be met through most prenatal vitamins. However, if you have iron deficiency or anemia, you’ll need higher doses of iron, managed by your doctor.
If you aren’t iron deficient, you shouldn’t take more than the recommended iron intake to avoid adverse side effects. These may include constipation, vomiting, and abnormally high hemoglobin levels.
4. Vitamin D
This fat-soluble vitamin is important for immune function, bone health, and cell division.
Vitamin D deficiency during pregnancy has been linked to an increased risk of cesarean section, preeclampsia, preterm birth, and gestational diabetes.
The recommended vitamin D intake during pregnancy is 600 IU or 15 mcg daily. However, some experts suggest that vitamin D needs during pregnancy are much higher.
Check in with your doctor regarding screening for vitamin D deficiency and proper supplementation.
Magnesium is a mineral involved in hundreds of chemical reactions in your body. It plays a critical role in immune, muscle, and nerve function.
Deficiency in this mineral during pregnancy may increase the risk of chronic hypertension and premature labor.
Some studies suggest that supplementing with magnesium may reduce the risk of complications like fetal growth restriction and preterm birth.
Ginger root is commonly used as a spice and herbal supplement.
In supplement form, you may have heard of it used to treat nausea caused by motion sickness, pregnancy, or chemotherapy.
A review of four studies suggested that ginger is both safe and effective for treating pregnancy-induced nausea and vomiting.
Nausea and vomiting are common during pregnancy, with up to 80 percent of women experiencing them in the first trimester.
Though ginger may help reduce this unpleasant pregnancy complication, more research is needed to identify the maximum safe dosage. Double check with your doctor to see if you need it.
Suggested read: 13 foods to eat when you’re pregnant
7. Fish oil
Fish oil contains docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), two essential fatty acids important for a baby’s brain development.
Supplementing with DHA and EPA in pregnancy might boost post-pregnancy brain development in your baby and decrease maternal depression, though research on this topic isn’t conclusive.
Although observational studies have shown improved cognitive function in the children of women who supplemented with fish oil during pregnancy, several controlled studies have failed to show a consistent benefit.
For example, one 2010 study involving 2,399 women found no difference in the cognitive function of infants whose mothers had supplemented with fish oil capsules containing 800 mg of DHA per day during pregnancy compared with infants whose mothers did not.
This study also found that supplementing with fish oil did not affect maternal depression.
However, the study did find that supplementing with fish oil protected against preterm delivery, and some evidence suggests that fish oil may benefit fetal eye development.
Maternal DHA levels are important for proper fetal development, and supplementing is considered safe. The jury is still out on whether taking fish oil during pregnancy is necessary.
To get DHA and EPA through food, it’s encouraged to consume two to three servings of low-mercury fish like salmon, sardines, or pollock per week.
Given increased general awareness of gut health, many parents-to-be turn to probiotics.
Probiotics are living microorganisms that are thought to benefit digestive health.
Many studies have shown that probiotics are safe to take during pregnancy, and no harmful side effects have been identified, aside from an extremely low risk of probiotic-induced infection.
Additionally, several studies have shown that supplementing with probiotics may reduce the risk of gestational diabetes, postpartum depression, and infant eczema and dermatitis.
Research on probiotic use in pregnancy is ongoing, and more about the role of probiotics in maternal and fetal health is sure to be discovered.
Choline plays a vital role in a baby’s brain development and helps to prevent abnormalities of the brain and spine.
The current recommended daily allowance of choline during pregnancy (450 mg per day) has been considered inadequate, and an intake closer to 930 mg per day is optimal.
Note that prenatal vitamins often don’t contain choline. Your doctor may recommend a separate choline supplement.
Supplements to avoid during pregnancy
While supplementing with some micronutrients and herbs is safe for pregnant women, many of them should be avoided in high amounts.
Always check with your doctor before adding additional supplements outside of any prenatal vitamins you may be taking.
1. Vitamin A
You’ll often find vitamin A in your prenatal vitamins since it’s so important. Although this vitamin is extremely important for fetal vision development and immune function, too much vitamin A can be harmful.
Since vitamin A is fat soluble, your body stores excess amounts in the liver.
This accumulation can have toxic effects on the body and lead to liver damage. It can even cause birth defects.
For example, excessive amounts of vitamin A during pregnancy has been shown to cause congenital birth abnormalities.
Between prenatal vitamins and foods, you should be able to get enough vitamin A, and additional supplementation outside of your prenatal vitamins is not advised.
2. Vitamin E
This fat-soluble vitamin plays many important roles in the body and is involved in gene expression and immune function.
While vitamin E is very important for health, it’s recommended that you don’t supplement with it.
Extra supplementation with vitamin E has not been shown to improve outcomes for either mothers or babies and may increase the risk of abdominal pain and premature rupture of the amniotic sack.
3. Black cohosh
A member of the buttercup family, black cohosh is a plant used for various purposes, including controlling hot flashes and menstrual cramps.
Taking this herb during pregnancy is unsafe, as it can cause uterine contractions, which could induce preterm labor.
Suggested read: Can you eat tuna while pregnant?
Black cohosh has also been found to cause liver damage in some people.
Goldenseal is a plant used as a dietary supplement to treat respiratory infections and diarrhea, although there’s little research on its effects and safety.
Goldenseal contains a berberine substance, which has been shown to worsen jaundice in infants. It can lead to kernicterus, a rare type of brain damage that can be fatal.
For these reasons, definitely avoid goldenseal.
5. Dong quai
Dong quai is a root used for over 1,000 years and is popular in traditional Chinese medicine.
Though it’s used to treat everything from menstrual cramps to high blood pressure, evidence regarding its efficacy and safety is lacking.
You should avoid dong quai, as it may stimulate uterine contractions, raising the risk of miscarriage.
Yohimbe is a supplement made from the bark of a tree native to Africa.
It’s used as an herbal remedy to treat various conditions, from erectile dysfunction to obesity.
This herb should never be used during pregnancy, as it has been associated with dangerous side effects like high blood pressure, heart attacks, and seizures.
7. Other herbal supplements that are considered unsafe during pregnancy
It’s best to avoid the following:
- saw palmetto
- red clover
- blue cohosh
Pregnancy is a time of growth and development, making health and nutrition a top priority. Taking the best care of that little one is the goal.
While some supplements can be helpful during pregnancy, many can cause dangerous side effects for you and your baby.
While supplementing with specific vitamins and minerals may help fill nutritional gaps, supplements are not meant to replace a healthy diet and lifestyle.
Nourishing your body with nutrient-dense foods, getting enough exercise and sleep, and minimizing stress is the best way to ensure a healthy pregnancy for you and your baby.
Although supplements can be necessary and helpful in certain circumstances, always check with your doctor regarding doses, safety, and potential risks and benefits.
Suggested read: Breastfeeding diet: What to eat while breastfeeding