Prenatal vitamin supplements are a highly recommended medication during pregnancy. They contain nutrients such as vitamins and minerals, which are an essential requirement for a healthy pregnancy and a healthy baby.

Special emphasis in the contents of the prenatal vitamins’ formulation is laid on folic acid, calcium, and iron, which are the most essential nutrients for pregnancy. That is the major difference from the usual multivitamins that we otherwise take.

All these and other nutrients are added to the medication in the right dose to make sure that the mother and baby get their recommended daily allowance (RDA) of nutrition.

However, remember that these supplements are an add-on to your nutritious pregnancy diet and not a replacement.

How are they different and why are prenatal vitamins necessary during pregnancy?

Though you may be having proper pregnancy nutrition, or though you may be on some multivitamins for some reason during pregnancy, prenatal supplements should replace the routine multivitamins that you are taking.

Secondly, they will also fill in any gaps and deficiencies your diet could be having. This is because the needs for certain nutrients are more during pregnancy due to the growing fetus and the physical changes in the mother.

The RDA (recommended daily allowance) of almost all nutrients increases during pregnancy and these prenatal supplements are formulated to fulfill these extra needs. The post on vitamins during pregnancy describes these additional nutritional vitamin needs.

Secondly, there cannot be anything easier than popping just one prenatal vitamin pill a day.

Though all nutrients are required in additional doses, the nutrients of special importance are folic acid, which is vitamin B9, and iron and calcium.

When should you start taking prenatal vitamins and for how long?

Prenatal vitamins or pregnancy vitamins are vitamin and mineral supplements, which the pregnant woman should take before, during pregnancy, and also during the post-delivery breastfeeding days.

By before pregnancy, we mean as soon as the woman has planned to become pregnant. The vital benefits include preventing any birth defects in the baby

Ideally, take prenatal vitamin supplements three months before you plan to conceive. This is because the nervous system of the baby starts developing in the first month of the pregnancy itself, probably before you realize that you are pregnant.

It is an insurance policy for your baby, ensuring that your body is well-stocked with essential nutrients that your baby is going to need from conception.

This ensures a healthy nutritional status for the woman when she conceives and contributes to a healthy and defect-free baby.

How to choose the best prenatal vitamin supplement for you?

Choosing the right prenatal vitamin supplement is best left to your doctor.

Extra intake of certain nutrients such as vitamin A can be harmful to the baby. Excess intake of preformed vitamin A or retinol can cause birth defects affecting the lungs, eyes, heart, or skull and therefore, the best prenatal vitamin supplements should contain the right proportion of the required nutrients. We have described them below.

What is in prenatal vitamins? Contents and their RDA in pregnancy

Your prenatal supplements will mainly contain adequate doses of vitamins and minerals to cater to your additional needs during pregnancy. They also make sure your baby will get its requirement in an adequate amount and at the right time.


  • Vitamin A – No more than 10,000 IU. More than this can be toxic. Look for beta-carotene; it is the safest source of vitamin A.
  • Vitamin B1 (Thiamine) – 3 mg
  • Vitamin B2 (Riboflavin) – 2 mg
  • Vitamin B3 (Niacin) – 20 mg
  • Vitamin B6 (Pyridoxine)
  • Vitamin B9 (Folic acid) – 400 micrograms (mcg)
  • Vitamin B12 (Cynocobalamin) – 6 mcg
  • Vitamin C – 70 mg
  • Vitamin D – 600 IU. + Make sure you get that 15 minutes of soft morning sun exposure every day.
  • Vitamin E – 10 mg
  • Vitamin K


  • Iron -27 mg
  • Calcium – 200 to 300 milligrams (mg)
  • Zinc – 15 mg.
  • Copper –0.9 mg
  • Selenium
  • Iodine – 150 micrograms

Omega 3 fatty acids

These are good fats and contribute heavily to the baby’s brain development before and after birth. You should know that the brain contains 60 percent fat.

If you are not getting your omega fats from the recommended two to three servings (8 to 12 ounces) of pregnancy-safe fish per week, you should consult your doctor and ask if you need to take an omega-3 fatty acid supplement.

Now let us elaborate what are the benefits of the important ingredients of prenatal vitamin supplements namely, folic acid, iron, calcium, and iodine.

Benefits of folic acid

Folic acid is essential for the proper development of the nervous system of the baby and for a healthy pregnancy. It prevents neural tube birth defects, which can affect the brain and spinal cord.

The importance of early intake of folic acid lies in the fact that neural tube defects can develop as early as 28 days after conception.

It is necessary that any woman who becomes pregnant should start taking 400 micrograms (mcg) of folic acid daily for the first three months of the pregnancy.

Its role is also important in the formation of cells, the development of DNA, and the formation of tissues.

It also promotes the formation of red blood cells. Taking adequate folic acid reduces the risk of neural defects in the baby by 70% and also greatly reduces the risk of preeclampsia in the pregnant woman.

Preeclampsia is a serious condition in which the pregnant woman develops high blood pressure. Due to its importance, many doctors prescribe separate folic acid supplements during pregnancy.

Even if you eat a lot of green leafy vegetables, nuts, beans, and citrus fruits that contain folic acid, supplements of folic acid are still required.

Benefits of Iron during pregnancy

During pregnancy, there is an increased risk of anemia due to increased blood volume, which increases the requirement for iron by almost 50%.

The red blood cells of the blood contain a protein called hemoglobin, a significant part of which is made of iron. This hemoglobin carries oxygen in the blood for supply to various parts of the body. Lack of iron, therefore, results in less oxygen being received by the body cells. The result is anemia.

Due to an increase in blood volume and circulation during pregnancy by almost 50%, the need for iron increases to make that much more hemoglobin. Besides the increased need by the fetus, having extra iron from the pregnant mother also helps to combat blood loss during delivery.

About two-thirds of iron in the body is stored in hemoglobin. It is important to fulfill this increased requirement in order to fuel the increased production of hemoglobin and to avoid anemia.

Towards the end of pregnancy, the baby too starts storing a good six months’ requirement of iron as it does not get enough of it from the mother’s milk. After six months, solid foods (which are often fortified) begin the iron supply to the infant.

Iron also helps in the development of muscles in the mother and baby.

Sufficient intake of iron also reduces the risk of premature delivery and low birth weight baby.

Benefits of Calcium in pregnancy

  • Calcium makes strong bones and teeth.
  • Prevents formation of blood clots.
  • Helps in the functioning of the nerves
  • Development of muscles.
  • When there is inadequate intake of calcium by the pregnant mother, calcium is drawn from her bones to fulfill the requirement of the developing fetus. A deficiency of calcium could, therefore, cause serious health conditions for the mother such as osteoporosis.
  • Calcium reduces the risk of hypertension and preeclampsia during pregnancy.

Importance of iodine

Iodine is essential for a healthy thyroid. A deficiency of iodine can lead to:

  • Miscarriage and stillbirth.
  • Stunted growth
  • The child can be mentally retarded
  • Loss of hearing


Prenatal vitamin supplements come as

  • Prenatal tablets or pills
  • Chewable prenatal vitamins
  • Liquid prenatal vitamins

You could use any form of these prenatal vitamins that best suit you.

OTC and prescription prenatal vitamins -Differences

Prenatal vitamins are available over the counter (OTC) as well as by prescription. The difference between the two forms is the concentration of some of the ingredients.

For example, prescription prenatal vitamins usually contain up to 1,000 micrograms of folic acid, which is the maximum you should take per day, while the OTC versions usually contain no more than 800 micrograms.

Similarly, prescription vitamins may have higher iron content, with 30 milligrams or more.

According to the American Pregnancy Association, you can endanger your baby’ and your health by taking inappropriate doses of synthetic vitamins. you should consult your doctor before you start taking any supplements.

Prenatal Vitamins with DHA

DHA is a docosahexaenoic acid which is an omega-3 fatty acid important for brain, eye, and heart health. The latest trend is to include DHA in prenatal supplements because most American diets are deficient in this nutrient.

This is because DHA is mostly found in fish and pregnant women are often asked to avoid fish due to fear of mercury contamination of certain types of fish.

DHA comes in a soft gel capsule form and you may take it separately.

Side Effects of Prenatal Vitamins

If you experience any side effects when taking these vitamins, you should seek the advice of your doctor who may then change either the vitamin brand with a lesser concentration of iron or its form (change over to either the liquid or chewable form).

The most common side effects include

  • Constipation
  • Darkened or green stools
  • Tarry stools due to the presence of blood.
  • Diarrhea
  • Nausea
  • Vomiting
  • Allergic reactions include skin rash, shortness of breath, and swelling of the mouth.

How to lessen the impact of the side effects?

  • You could take the prenatal supplement with water or juice (not milk or soda) after meals at night
  • Eat plenty of fiber foods
  • Drink plenty of water
  • Add physical activity to your routine (read exercise and pregnancy)
  • Take a stool softener if you feel constipated.

Where Can You Get Prenatal Vitamins?

Prenatal vitamins are available at drug stores as OTC products and also by prescription.