Can taking prenatal vitamins change your menstrual cycle

Q: Can prenatal vitamins mess up your period?

Vitamins, prenatal or otherwise, cant regulate your period. Its possible for you to have very irregular or absent periods if youre severely undernourished or are of very low body weight, but in such cases the problem has to do with low body fat rather than low vitamin levels.

Q: What are the side effects of taking prenatal vitamins when not pregnant?

Prenatal vitamins arent recommended for long-term use for the following reasons:.

You may be tempted to take prenatal vitamins because of unproven claims that they promote thicker hair and stronger nails. However, if you're not pregnant and not planning to become pregnant, high levels of certain nutrients over a long period of time may actually be more harmful than helpful.

Table of Contents Show

From Mayo Clinic to your inbox
Can prenatal vitamins mess up your period?
What are the side effects of taking prenatal vitamins when not pregnant?
Can vitamins change your menstrual cycle?
Can vitamin supplements delay your period?

Prenatal vitamins are formulated specifically for women who are pregnant or trying to become pregnant, and women who are breast-feeding, with particular emphasis on:

Folic acid. To reduce the risk of having a child with neural tube defects, it's recommended that women who are trying to become pregnant get 400 to 800 micrograms (mcg) of folate or folic acid a day through diet and supplements. Other healthy adults — both men and women — need only 400 mcg a day. While uncommon, getting too much folic acid by taking supplements can mask the symptoms of vitamin B-12 deficiency and delay diagnosis and treatment.
Iron. During pregnancy, the recommended intake of iron is 27 milligrams (mg) a day. Women between the ages of 19 and 50 who aren't pregnant need only 18 mg a day, and women age 51 and older and all adult men need only 8 mg a day. Getting too much iron can be toxic because it can build up in your body, causing constipation, nausea, vomiting, diarrhea and, in severe cases, possibly death.
Calcium. Pregnant adult women and healthy men and women ages 19 to 50 all need 1,000 mg a day. Men and women age 51 and older need 1,000 mg a day and 1,200 mg a day, respectively. Because prenatal vitamins are intended to supplement calcium you get in your diet, they generally contain only 200 to 300 mg of calcium. If you rely on prenatal vitamins to meet your calcium needs, you likely won't get enough, raising your risk of osteoporosis and other health problems.

Generally, if you eat a healthy, balanced diet, taking multivitamins of any sort isn't necessary.

From Mayo Clinic to your inbox

Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

Aug. 27, 2020

2015-2020 Dietary Guidelines for Americans. U.S. Department of Health and Human Services and U.S. Department of Agriculture. http://health.gov/dietaryguidelines/2015/guidelines. Accessed March 20, 2017.
Dietary supplement fact sheet: Folate. Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/. Accessed March 20, 2017.
Dietary supplement fact sheet: Iron. Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/. Accessed March 20, 2017.
Dietary supplement fact sheet: Calcium. Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/. Accessed March 20, 2017.
Questions to ask before taking vitamin and mineral supplements. Nutrition.gov. https://www.nutrition.gov/dietary-supplements/questions-ask-taking-vitamin-and-mineral-supplements. Accessed March 20, 2017.
Nutrition during pregnancy. The American College of Obstetricians and Gynecologists. http://www.acog.org/Patients/FAQs/Nutrition-During-Pregnancy#extra. Accessed June 12, 2017.
AskMayoExpert. Preconception care. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2017.
Wick M (expert opinion). Mayo Clinic, Rochester, Minn. Jan. 6, 2017.
U.S. Preventive Services Task Force. Folic acid supplementation for the prevention neural tube defects. Journal of the American Medical Association. 2017;317:183.
Prenatal care, routine. Bloomington, Minn.: Institute of Clinical Systems Improvement. https://www.icsi.org/guidelines__more/catalog_guidelines_and_more/catalog_guidelines/catalog_womens_health_guidelines/prenatal/. Accessed June 21, 2017.

See more Expert Answers