Supplements in Pregnancy: All You Need to Know

At every stage of life, a balanced diet is the best way to get the nutrients, but it is critical during pregnancy. Vitamins and supplements in pregnancy can be beneficial. Your doctor may recommend prenatal vitamin supplements, plus additional vitamins or minerals if there are any deficiencies.

1. Iron

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During pregnancy, the need for iron increases significantly as the volume of maternal blood increases by almost 50 percent.

Iron is essential to the fetus and placenta for carrying oxygen. Pregnancy anemia is associated with premature delivery, maternal depression, and infant anemia.

Many prenatal vitamins will meet the recommended intake of 27 mg of iron per day. Therefore, pregnant women with iron deficiency or anemia require higher doses of iron, controlled by their doctor.

Pregnant women not deficient in iron should not take more than the normal iron intake to prevent adverse side effects. Such side effects are Constipation, diarrhea and high levels of hemoglobin.

2. Vitamin D

This fat-soluble vitamin is essential for immune function, cell division, and bone health. During pregnancy, vitamin D deficiency increases the risk of cesarean section, preeclampsia, premature birth and gestational diabetes.

The current recommended vitamin D supplements intake during pregnancy is 600 IU per day. Some experts, however, say that vitamin D requirements are much higher during pregnancy.

All women who are pregnant should talk to their doctor about vitamin D deficiency.

3. Folate

Folate is a B vitamin that plays an integral role in the synthesis of DNA, the production of red blood cells and the growth and development of the fetus.

Folic acid is the synthetic shape of folate available in many supplements. It becomes the active folate form, L-methyl folate, in the body.

To reduce the risk of neural tube defects and congenital abnormalities, pregnant women should take 600 ug of folate or folic acid per day.

A review of five randomized studies, including 6,105 women, associated with a reduced risk of neural tube defects supplementing with folic acid daily. There were no negative side effects.

While you can get adequate folate from your diet, many women do not eat enough folate-rich foods, which lead to supplementation.

For pregnant women, especially those with a genetic mutation of MTHFR, it may be wise to choose a supplement that contains L-methyl folate to ensure maximum uptake.

4. Probiotics

Probiotics are living microorganisms that may benefit digestive health. Several studies have shown that probiotics are safe to take during pregnancy, and no adverse side effects have been reported.

In addition, several studies have found that probiotic supplementation may reduce the risk of gestational diabetes, postpartum depression, and infant eczema and dermatitis.

5. Fish Oil

Fish oil contains two essential fatty acids DHA and EPA, which are important for the development of the fetal brain. DHA and EPA supplements during pregnancy may boost the development of the infant’s brain and decrease maternal depression, although research on this subject is not leading to a firm conclusion.

Although observational studies have shown enhanced cognitive function in women’s children who supplemented with fish oil during pregnancy. However, several controlled studies have failed to show a significant benefit.

For example, one study involving 2,399 women found no difference in the cognitive function of infants whose mothers had supplemented throughout pregnancy with fish oil capsules containing 800 mg of DHA per day compared to infants whose mothers had not.

This study also found no effect on maternal depression when supplemented with fish oil. The study found that supplementing fish oil protected from premature delivery, and some evidence suggests that fish oil may aid the development of fetal eyes.

However, pregnant women should eat two to three servings of low-mercury fish such as salmon, sardines or pollock per week to get DHA and EPA via diet.

6. Magnesium

Magnesium is a mineral in your body that has undergone hundreds of chemical reactions. Plays critical roles in the action of immune muscle and nerve.

Deficiency of this mineral can increase the risk of chronic hypertension and premature labor during pregnancy.

Some studies suggest that magnesium supplementation can lower the risk of such as restrictions on fetal growth and preterm birth.

7. Prenatal Vitamins

Prenatal vitamins are multivitamins particularly essential during pregnancy to meet the increased demand for micronutrients. Women can take it before birth, during pregnancy and lactation.

Observational studies have shown that prenatal vitamin supplementation reduces the risk of preterm birth and preeclampsia. Preeclampsia is a condition characterized by high blood pressure and likely protein in the urine.

While prenatal vitamins cannot replace a healthy diet, they help to prevent nutritional gaps by providing extra micronutrients are in high demand throughout pregnancy.

Since prenatal vitamins contain the vitamins and minerals which pregnant women need, it may not be necessary to take additional vitamin or mineral supplements unless your doctor suggests.

Supplements to Avoid During Pregnancy

Although it is safe for pregnant women to supplement with some vitamins and minerals. However, certain supplements should be avoided in pregnancy.

Vitamin A Supplements

Although vitamin A is important for fetal vision and immune function, but too much vitamin, A can be harmful. The body stores excess amounts of vitamin A in the liver.

This accumulation can have adverse effects on the body, which can cause damage to the liver. For example, excessive amounts of vitamin A supplements can cause congenital birth defects during pregnancy.

Pregnant women should get enough vitamin A from prenatal vitamins and diet to prevent deficiency, although they don’t need extra vitamin A supplementation.

Vitamin E Supplements

The fat-soluble vitamin plays many important roles in the body and includes the expression of genes and the immune function.

While vitamin E is very important for health, pregnant women should not supplement with it.

Vitamin E supplementation has no outcomes for either mothers or babies, and may instead increase the risk of abdominal pain and amniotic sac premature rupture.

Other Supplements to Avoid

Blue Cohosh, Black Cohosh, Yarrow, Wormwood, Pennyroyal, Ephedra, Mugwort, Goldenseal, Dong Quai, Yohimbe, Saw palmetto, Tansy, Red clover, Angelica

Bottom Line

Pregnancy is a period of growth and development which gives top priority to health and nutrition. While some supplements may be beneficial during pregnancy, many can cause both pregnant women and their baby dangerous side effects. The best way to ensure a healthy pregnancy for you and your baby is to feed your body with nutrient-dense foods and get enough exercise and sleep and reduce stress. Always check with your doctor about doses, safety, and risks and benefits.

Frequently Asked Questions

Why pregnancy increases the need for nutrients?

Vitamins and minerals promote maternal and fetal growth at each pregnancy stage and are necessary to support critical functions such as cell growth and cell signaling. Females carrying over one baby have higher micronutrient requirements than women carrying one baby. It often requires supplementation to ensure optimal nutrition for both the mother and her baby.

Can I take herbal supplements during pregnancy?

While some herbs may help with common complications of pregnancy such as nausea and stomach upset, some may be harmful to both mother and fetus. Unfortunately, there is not much research regarding pregnant women’s use of herbal supplements, and much is unclear about how the supplements will affect expectant mothers.

Why are vitamins and minerals important in my diet?

Vitamins and minerals play important roles in every part of your body. You’ll need more folic acid and iron during pregnancy than a woman who isn’t pregnant.

Are oils and fats part of a healthy diet during pregnancy?

The fat you eat during pregnancy provides nutrition and help build several fetal organs and the placenta. Most of your dietary fats and oils will come from plant sources. Reduce heavy fat, such as animal fats.


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Naeem Durrani BSc
I am a retired pharmacist, nutrition expert, journalist, and more. My interests include medical research, and the scientific evidence around effective wellness practices, which empower people to transform their lives.

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