Prenatal Vitamins

A close up of a pregnant woman holding her prenatal vitamins in her left hand while holding a cup of water in her right hand.
Prenatal vitamins are vital for both mother and baby. Oscar Wong / Getty Images

Prenatal vitamins are multivitamins and mineral supplements for use during pregnancy and nursing.



To avoid stomach irritation, you can take prenatal vitamins

with food or with a full glass of water or milk, unless your


doctor directs you otherwise.

If you miss a dose of the prenatal vitamins, take the missed dose as soon as possible after you remember. However, if it is almost time for the next dose, do not take the missed dose at all; just return to your regular dosing schedule. Do not double the next dose.

Prenatal Vitamin Side Effects

Minor: Constipation, diarrhea, nausea, stomach upset, or vomiting. These side effects should disappear as your body adjusts to the prenatal vitamins.

To relieve constipation, increase the amount of fiber in your diet (fresh fruits and vegetables, salads, bran, and whole-grain breads), exercise, and drink more water (unless your doctor directs you to do otherwise).

Black stools are a normal consequence of iron therapy and do not indicate that a problem has developed from the vitamin therapy.

Major: Tell your doctor about any side effects that are persistent or particularly bothersome. IT IS ESPECIALLY IMPORTANT TO TELL YOUR DOCTOR about bloody or tarry stools or severe abdominal pain.


Prenatal Vitamin Interactions

Prenatal vitamins should not interact with other medications if they are used according to directions. However, be sure that your doctor knows about any medications or supplements that you are currently taking.


Prenatal Vitamin Warnings

  • Tell your doctor about unusual or allergic reactions you have had to any medications, especially to any vitamin, mineral, or iron products.
  • Be sure to tell your doctor if you have ever had bone disease, liver disease, kidney disease, or stomach ulcers.
  • Because prenatal vitamins may mask the symptoms of pernicious anemia, they should be used only under a doctor's supervision.


To learn more about the topics on this page, try the following links:

  • To learn more about pregnancy and delivery, try How Pregnancy Works.
  • To find out more about other prenatal procedures, go to How Prenatal Testing Works.
  • Our Vitamins page can lead you to all sorts of information about vitamins, how they work, and how much you need in your diet. //]]]]> ]]>