When Do I Stop Taking Prenatal Vitamins?

When you're thinking about getting pregnant, there's an important first step of your journey: prenatal vitamins.

Your ob-gyn can recommend the best prenatal vitamins for you, depending on your health and nutritional needs.

"The main reason for taking prenatal vitamins is for the folic acid," Valerie Joy Altmann, MD, an attending ob-gyn physician at Long Island Jewish Medical Center and Assistant Professor at Hofstra Northwell School of Medicine tells LIVESTRONG.com. Getting enough folic acid helps prevent neural tube defects, she says, which are problems in the development of the brain and spinal cord, according to the American College of Obstetricians and Gynecologists.

But prenatal vitamins also contain recommended doses of other essential nutrients and vitamins for pregnancy, including calcium, iron, vitamin A, vitamin D and more, according to the American College of Obstetricians and Gynecologists.

But understanding when to stop taking prenatal vitamins may not always be as clear. Here's what you need to know.

Dr. Altmann recommends starting prenatal vitamins at least one month before conception as a step toward becoming pregnant.

"It's always a delicate balance asking a patient if they are planning to conceive within the next year," Dr. Altmann says. "You try to understand. Someone who is not taking contraception, then I usually ask them, 'Are you planning on conceiving, being that you are not preventing a pregnancy?' That's a springboard for me to start prenatal counseling."

She recommends pregnant people continue to take a folic acid prenatal vitamin for at least 3 months into the pregnancy — "That is the most crucial time when neural tube defects could occur," she says — but typically throughout the whole pregnancy. "It's good nutritionally for the patient," she adds.

In fact, most people typically continue with their prenatals throughout the whole pregnancy ‌and‌ while breastfeeding, she says. "Most people stop taking them after they stop nursing," she says.

If you stop before then, however, there's no severe risk to you or your child, as long as you kept up with your prenatals for at least the first three months of your pregnancy and you're eating a balanced diet, she says.

Prenatal vitamins have all the recommended nutrients a person needs before and during a pregnancy, such as folic acid and iron, so the ACOG recommends taking them before and during pregnancy.

"You can sometimes describe the fetus almost as a parasite," Dr. Altmann says. "The fetus is going to take all the nutrients" from the birthing parent. "That means they need to get enough calcium and vitamin D for their own bone health, for example, and enough iron for their own energy levels," she says.

Most healthy pregnant people can select a prenatal vitamin with 400 micrograms of folic acid, according to the Centers for Disease Control and Prevention (CDC). This is typically taken daily.

There isn't necessarily a best time of day to take them; rather, whenever you'll remember is a good time to take prenatals, Dr. Altmann says. "There's no detrimental effects if you take it at different times every day. It's just easier to remember to take something when you have a set time to take it."

Don't worry too much if you forget occasionally, either, she says, but especially during the first three months of pregnancy, it's best to try to pop your prenatals regularly.

There are a few medical reasons why a person might need higher doses of folic acid during pregnancy.

"If a patient has a history of carrying a child with a neural tube defect, then the recommendation is 4 milligrams," Dr. Altmann says. (That's 10 times the usual amount.) "If somebody is on seizure medication, we also recommend that they take 4 milligrams because the seizure medication puts them at an increased risk for neural tube defects."

Other pregnant people may need to supplement with more of certain vitamins depending on their own risk of nutritional deficiencies, according to Youyin Choy, MD, FACOG, obstetrician-gynecologist and assistant professor in the Raquel and Jaime Gilinski Department of Obstetrics, Gynecology and Reproductive Science at the Icahn School of Medicine at Mount Sinai.

These include:

• People pregnant with multiples (twins or triplets)
• Smokers
• Teens
• Vegetarians or vegans
• People who use drugs or alcohol
• People who have had bariatric surgery
• People with Crohn's disease

For people with these kinds of nutritional deficiencies, there are no specific guidelines on when to stop taking prenatal vitamins, Dr. Choy says. Some may continue with "short-term supplements such as iron pills if they have postpartum anemia or excessive blood loss — in the case of twins or multiples — for about one or two months until they feel better," for example. Or they can continue with prenatal vitamins while breastfeeding, she says.

It's not necessary to keep taking prenatal vitamins while breastfeeding, Dr. Choy says.

"It all depends on the individual preference and their diet," she says. "Once a baby is delivered, a postpartum patient should be able to eat a well-balanced diet and replenish and restore the nutrients used during the pregnancy."

That said, fat-soluble vitamins such as A and D secrete through breastmilk, "so if they want to take that until they stop breastfeeding, that is absolutely fine," Dr. Choy adds. (Some people switch to postnatal vitamins at this time.)

Part of the reason you may be curious about when you can stop taking prenatals may be the side effects you're experiencing.

Dr. Choy says there are three main side effects of prenatal vitamins she sees in her patients. "A major problem is constipation from iron in the prenatal vitamin. Some patients get nauseous and have vomiting."

She recommends trying different vitamins to see what agrees most with your body and digestion. Your ob-gyn can help recommend some options, or you can try shopping from our list of the best prenatal vitamins or prenatal vitamins that don't cause constipation.