Can Prenatal Vitamins Make You Sick? Managing Nausea From Prenatals
Are Prenatal vitamins making you sick? Let’s talk about why prenatal vitamins cause nausea and how to manage this when pregnant or trying to conceive.
Nausea is a well-documented 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. It’s a different story if your 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.
Why Does Pregnancy Cause Nausea?
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. [2-3] Another theory is that nausea and vomiting during pregnancy is an evolutionary adaptation to protect a woman and her fetus from potentially dangerous foods. 
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.
Preventing Nausea With Prenatal Vitamins
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. [5-6] Why? The answer is unclear. The investigators of these studies speculated that simply being at optimal nutritional status at the beginning of pregnancy or increasing vitamin B6 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 nausea and vomiting in pregnancy and decreasing the severity if it does occur.
But even the best-laid plans don’t always pan out—some women are simply predisposed to nausea in pregnancy. Whether you’re experiencing nausea and vomiting because of your prenatal vitamin or if your prenatal is making your already existing symptoms worse, there are some tips and tricks you can try to help manage your nausea.
How to Reduce Nausea From Prenatal Vitamins
Pregnancy and TTC can be hard enough without the added struggle of nausea. Fortunately there are ways to curb nausea while still getting all the vital nutrients you need.
Change Your Dose
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 27 mg 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 vitamin B6 or has a low dose, try switching to one that has a higher dose. Additionally, consider incorporating remedies like our ginger and vitamin B6 gummies for nausea into your routine, as they have shown to provide effective relief from pregnancy-related discomfort.
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 vitamins kinder on your stomach. This can be a little challenging if you’re already dealing with nausea at baseline from your pregnancy. Nausea from 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, which isn't a good idea. If you’re going through this, 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 under controlled 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 usually exclusively in the mornings but for some women, it can be. For others, nausea can 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 as to not exacerbate your symptoms.Sometimes, the size or dose of the pill is the issue. If that's the case, try finding a prenatal formulation that is split up into multiple doses throughout the day so you're not just taking one giant pill that can overwhelm your stomach. For certain pills (like tablets that don't have a special coating), you can also break them in half. 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 Substitues and Nausea Remedies
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 folate) or a Prenatal Gummy Vitamin in place of larger prenatal vitamins.
You could also give nautral remedies a try with ginger root and peppermint. Natalist Nausea Relief Tea is made for nausea relief any time of the day, and it's organic! Natalist also offers Anti-Nausea Gummies made with vitamin B12 and ginger.
And if you just can't stomach any vitamins at all, at least make sure you’re getting enough folate (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. Find it bundled with other pregnancy symptom-relieving products in our pregnancy gift basket.
- Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin No. 189: Nausea And Vomiting Of Pregnancy. Obstet Gynecol. 2018;131(1):e15-e30. doi:10.1097/AOG.0000000000002456
- Bernstein L, Pike MC, Lobo RA, Depue RH, Ross RK, Henderson BE. Cigarette smoking in pregnancy results in marked decrease in maternal hCG and oestradiol levels. Br J Obstet Gynaecol. 1989;96(1):92-96. doi:10.1111/j.1471-0528.1989.tb01582.x
- Depue RH, Bernstein L, Ross RK, Judd HL, Henderson BE. Hyperemesis gravidarum in relation to estradiol levels, pregnancy outcome, and other maternal factors: a seroepidemiologic study. Am J Obstet Gynecol. 1987;156(5):1137-1141. doi:10.1016/0002-9378(87)90126-8
- Sherman PW, Flaxman SM. Nausea and vomiting of pregnancy in an evolutionary perspective. Am J Obstet Gynecol. 2002;186(5 Suppl Understanding):S190-S197. doi:10.1067/mob.2002.122593
- Czeizel AE, Dudas I, Fritz G, Técsöi A, Hanck A, Kunovits G. The effect of periconceptional multivitamin-mineral supplementation on vertigo, nausea and vomiting in the first trimester of pregnancy. Arch Gynecol Obstet. 1992;251(4):181-185. doi:10.1007/BF02718384
- Emelianova S, Mazzotta P, Einarson A, Koren G. Prevalence and severity of nausea and vomiting of pregnancy and effect of vitamin supplementation. Clin Invest Med. 1999;22(3):106-110.
- Nutrition During Pregnancy. FAQ 001. American College of Obstetricians and Gynecologists. June 2023. URL.