Prenatal Vitamins: Everything You Need to Know

Prenatal vitamins help meet the physiological changes during pregnancy. Let's see what they are and what the scientists say.
Prenatal Vitamins: Everything You Need to Know
Diego Pereira

Reviewed and approved by el médico Diego Pereira.

Last update: 03 March, 2023

During pregnancy, a series of physiological changes occur to ensure the normal development and health of the fetus. The changes are very varied, such as weight gain (between 11 and 16 kilograms – 24-34 lbs), increased hormonal production, cardiac and hematological changes, increased oxygen demand, and changes in the gastrointestinal system. Nutritional needs increase to support all of these changes. Prenatal vitamins are used as part of this support plan.

Although you might think that a balanced diet is enough to receive all the nutritional needs during pregnancy, the truth is that this isn’t always the case. For example, experts say that some deficiencies particularly affect pregnant women, such as vitamin D or iron. Let’s see what prenatal vitamins are, along with the recommendations for their intake.

Characteristics of prenatal vitamins

The nutritional status of the fetus depends mainly on maternal intake. It has been known for years that nutritional deficiencies can cause malformations and health problems for both the pregnant woman and the fetus.

Changes in the diet are, for their part, a central component to guarantee their own health and that of their offspring. Prenatal vitamins, in supplement form, are used as a complement and support.

The use of multivitamins during pregnancy is very common. In fact, according to recent estimates, between 78% and 98% of pregnant women in the United States, Canada and Australia use them.

It is important to note that the use of prenatal vitamins is not a substitute for a balanced diet. We must also point out that there’s a recommended daily amount for its intake.

According to the American College of Obstetricians and Gynecologists, exceeding the recommended amount of prenatal vitamins per day is contraindicated. Certain multivitamin ingredients, such as vitamin A, can cause birth defects in high doses. The obstetrician will recommend the specific dose according to personal needs, so their instructions must be followed at all times.

As researchers point out, there are several types of prenatal vitamins. The most common are iron and folic acid supplements (known as APIs), supplements with lipid-based nutrients (known as LNS), multiple micronutrient (MMN) supplements, and individual supplements. They are recommended before, during, and even after pregnancy. We reiterate that the obstetrician’s recommendations should be considered at all times.

What prenatal vitamins should you take?

The catalog of nutrients required during pregnancy is very varied. However, in the following paragraphs, we’re going to focus on those that are considered essential.

Most of them can be obtained through a balanced diet, but the intake of supplements guarantees the required daily intake. Let’s see what prenatal vitamins you should take.

Folic acid

Prenatal vitamins include folic acid.
Regular intake of folic acid supplements during pregnancy has been shown to prevent many birth defects.

Taking folic acid can help prevent birth defects that could affect the baby’s brain and spinal cord. Similarly, it also supports the overall growth and development of the fetus and placenta.

You can get folic acid in fortified cereal, enriched pasta and bread, dark green leafy vegetables, peanuts, orange juice, and beans (among others).

Its intake is recommended before becoming pregnant (one month before) and should then be postponed until the 12th week of gestation. The recommended dose is 600 micrograms per day, but, for supplements, a maximum of 400 micrograms is suggested. This is because, in theory, the remaining 200 micrograms are acquired through a balanced diet.


Calcium is an essential mineral that forms the bones and teeth of the fetus. Increasing its intake also prevents the mother from losing bone density, since a good part of what she consumes is transferred to the fetus.

The best sources of calcium are dairy products. Broccoli, cereals, fortified breads and juices, almonds and sesame seeds, sardines with bones, and dark green leafy vegetables are also rich sources.

Women under the age of 18 require 1,300 milligrams of calcium per day, while women over the age of 19 require 1,000 milligrams. Calcium supplements for pregnant women have become very popular, initially due to the problems many have tolerating dairy products. Consult your specialist in case you require a higher dose of this supplement.


The best sources of natural iron are beans, lentils, beef, fortified breakfast cereals, turkey, liver, and shrimp. In the same way, some foods encourage its absorption, among which grapefruits, strawberries, oranges, broccoli and peppers are the main ones. On average, pregnant women require 27 milligrams per day.

Iron deficiency anemia in pregnancy is very common, and can be prevented by taking supplements. In very simple terms, iron helps the body make more red blood cells. These, in turn, help send more oxygenated blood to the developing fetus. Experts warn that its excess can cause problems in pregnancy, so the suggested dose should never be exceeded.


Evidence indicates that iodine deficiency during pregnancy leads to maternal and fetal hypothyroidism and associated serious adverse health effects, such as cretinism and growth retardation.

It is also known that even a small excess is associated with complications, so prenatal iodine supplements should be kept at the standard dose at all times. That is, an average of 220 micrograms during the day.


Choline is a nutrient that contributes to fetal brain development, which may help prevent certain common birth defects. Most of it is obtained through food.

Chicken, peanuts, beef, soy products, eggs, and milk are your best sources. Not all prenatal supplements contain choline, so choose one carefully.

Vitamin A

Researchers have found that vitamin A is essential during pregnancy. Among other things, it helps the fetal eye health and the development of other organs, the skeleton, and the maintenance of the fetal immune system.

Its best natural sources are green leafy vegetables, orange and yellow vegetables, tomatoes, beef liver, milk, and eggs. On average, pregnant women require 750 micrograms per day.

Vitamin C

Prenatal vitamins have benefits.
There are various readily available foods that contain abundant amounts of vitamin C, in addition to other micronutrients.

Experts warn that there are no conclusive results that support the intake of daily supplementation with vitamin C. It’s thought that it may help prevent premature rupture of the membranes, preeclampsia, and fetal or neonatal death; but the truth is that the evidence isn’t solid.

Citrus fruits and juices, strawberries, broccoli, and tomatoes are your best natural sources. Pregnant women require an average of 85 grams per day to meet requirements.

Discover more here: The Dangers of Vitamin Overdose

Vitamin D

Vitamin D works together with calcium to help the development of bones and teeth in the fetus. Similarly, it’s essential for healthy skin and eyesight.

Fortified milk, salmon, fish liver oils, and egg yolks are some of its sources. Experts recommend both pregnant and non-pregnant women an average of 400 to 600 micrograms per day.

Vitamin B6

Vitamin B6 intake during pregnancy has been associated with a higher birth weight and a lower incidence of preeclampsia and preterm birth. Its best natural sources are tuna, salmon, beef, pork, nuts, and whole grains. Pregnant women require 2 milligrams of vitamin B6 daily.

B12 vitamin

Evidence indicates that vitamin B12 deficiency during gestation contributes to poor growth and neurodevelopment. Meat, fish, and milk are some of its natural sources. The daily demand for vitamin B12 in pregnant women ranges from 2.6 micrograms per day.

These are just some of the prenatal vitamins that are essential for a healthy pregnancy. Most of them are obtained through a balanced diet, but the intake of vitamin supplements is recommended in most cases. Consult with your specialist which of them you should take, what dose, and what type of diet to implement.

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