Prenatal Vitamins and Nausea

Wondering if prenatal vitamins will make you feel sick? Struggling with nausea right now and looking for ways to reduce symptoms? Get our tips.

Dr. Mare Mbaye, Natalist

Nausea is a well-known symptom of pregnancy, especially in the first trimester. “Morning sickness” is very common, occurring in up to 80% of expectant mothers. The name can be misleading however, since morning sickness typically occurs throughout the whole day, rather than just in the early hours. Bummer, I know.

While nausea is definitely unpleasant, it is not harmful to a pregnancy. Of course, it’s a different story if the nausea gets to a point where you are unable to keep anything down and start to lose weight. In that case, it’s imperative that you see your provider to make sure you don’t have a more severe form of nausea in pregnancy known as hyperemesis gravidarum.

There are several potential theories for why nausea in pregnancy occurs. Hormones are thought to be one reason, specifically human chorionic gonadotropin (HCG). Peak levels of HCG seem to coincide with when many women have their most severe nausea and vomiting symptoms. Estrogen is also a potential cause of nausea and vomiting in pregnancy. Studies have shown that these symptoms tend to be worse if estrogen levels are high. Another theory is that nausea and vomiting of pregnancy is an evolutionary adaptation that developed to protect a woman and her fetus from potentially dangerous foods. Finally, there is ongoing research looking at severe stress as a cause for these symptoms.

Regardless of why it happens, nausea and vomiting in pregnancy can be quite the battle depending on its severity. This can be further exacerbated when you add having to take a prenatal vitamin to that mix, especially since vitamins tend to come in the horse pill variety… bleh.

Our goal with treating nausea and vomiting in pregnancy to prevent it from happening in the first place. A couple of studies have found that women who were taking vitamins at the time of conception were less likely to need medical attention for nausea and vomiting. Why? The answer to that is unclear. The investigators of these studies speculated that simply being at optimal nutritional status at the beginning of the pregnancy or increasing vitamin B6 (pyridoxine) intake may decrease the incidence of vomiting in some pregnant women. As a result, the standard recommendation to take prenatal vitamins before conception may serve an additional purpose by possibly reducing the chances of getting nausea and vomiting in pregnancy in the first place and decreasing the severity if it does occur.

But even the best laid plans don’t always work and some women are simply more predisposed to nausea in pregnancy. Whether you’re experiencing nausea and vomiting because of your prenatal vitamin or your prenatal is making your already existing symptoms worse, here are some tips and tricks for how to navigate the situation.

Play around with the supplement doses (NOT the folic acid though!)

In and of themselves, prenatal vitamins can cause some degree of nausea. More often than not, the culprit is iron. If your prenatal vitamin consistently makes you feel nauseated, check the label — the recommended amount of iron per the American College of Obstetricians and Gynecologists (ACOG) and the National Institutes of Health (NIH) is 27mg per day. If your prenatal has more than that, try switching to one with a lower dose (as long as you weren’t placed on the higher dose because of anemia). If that still doesn’t help, ask your provider whether you can switch to a prenatal vitamin without iron during your first trimester and get iron from food sources instead.

As mentioned earlier, increasing vitamin B6 intake is associated with decreased nausea and vomiting. If your prenatal vitamin doesn’t have any vitamin B6 or has a low dose, try switching to one that has a higher dose.

Take your prenatal vitamin with food

Another reason your prenatal vitamin could make you feel more nauseated is if you’re taking it on an empty stomach. With few exceptions, taking any kind of vitamin or pill on an empty stomach can make you feel sick. Even something as small as a smoothie, yogurt or soup and crackers can make the prenatal vitamin kinder on your stomach. This can be a little challenging if you’re already dealing with nausea at baseline from your pregnancy. The nausea of pregnancy keeps you from eating, so you are forced to take your prenatal on an empty stomach, which makes you more nauseated and a vicious cycle is begun. Eventually, some women quit taking their prenatal vitamins altogether. If you’re going through this situation, and can’t stomach any food at all, bring it up to your provider. They may be able to help find ways to get your nausea controlled enough to allow you to eat better.

Change your timing

The time of day that you take your prenatal can also impact how much nausea you experience. As mentioned before morning sickness isn’t exclusively in the mornings, however for some women it is. For others, nausea can be at its worst throughout the day but may improve by the time the end of the day rolls around. If your nausea improves at a particular time of day, try taking your prenatal then so as to not exacerbate your symptoms.

Sometimes, the size or dose of the pill is the issue. If that’s the case, you can break your vitamin in half and take it as divided doses several hours apart. Taking a half dose in the morning and at night may be easier on the stomach and is completely alright to do since the exact time of day that you take your prenatals is not that important (See When Should I Start Taking Prenatals).

Try other substitutes

If none of the above tricks help, it’s important to talk to your doctor about alternative options. Some women are able to substitute two over the counter chewable children’s vitamins (with additional folic acid) in place of one big prenatal vitamin.

And if you just can’t stomach any vitamins at all, at least make sure you’re getting enough folic acid (especially in the first trimester) in order to reduce the risk of neural tube defects, which are serious birth defects of the brain and spine.

All of these tips are easy to try but the ultimate goal is to find an appropriate prenatal vitamin that you can tolerate. Experiment with the ideas above and make sure to have an open conversation with your provider to make sure your pregnancy is being supported in the best way possible.

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Image from studio somee.

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