what makes birth control less effective

What Makes Birth Control Less Effective

Dr. Jolene BrightenPublished: Last Reviewed: Birth Control, Hormonal Birth Control, Side Effects

Many women often wonder if taking supplements can interfere with the effectiveness of their birth control pills. The short answer is that while most supplements do not interfere with birth control, it's still important to be informed about potential interactions—such as those that can occur when taking medications with birth control.

Birth control pills work primarily by flooding the system with a high enough amount of hormone that the brain no longer communicates with the ovaries to mature and ovulate an egg. This is how they prevent ovulation and pregnancy. 

While most vitamins and minerals do not directly affect the efficacy of birth control pills, certain supplements warrant a closer examination due to their potential to interact with how your body processes these medications.

This article will explore what happens in the body when you take birth control pills along with common supplements, such as vitamins, minerals, and herbs, and provide clarity about how certain drugs and even timing can impact birth control's effects.

Can Vitamin and Mineral Supplements Interact With Birth Control Pills?

vitamins that affect birth control pills

Most vitamins, such as vitamins B and vitamins C, A, and E, do not affect birth control pills. This means that if you take a daily multivitamin, which typically provides a range of essential nutrients, you don't have to worry about it reducing birth control's effects.

While most supplements will not directly impact the effectiveness of birth control pills, they do play essential roles in maintaining overall health, which can indirectly influence how your body responds to and metabolizes these contraceptives. For instance:

  • Vitamin C: Increases estrogen absorption. High doses might increase estrogen levels, but not to a degree that would impact birth control effectiveness.
  • Vitamin B6: Can affect hormone metabolism but doesn't decrease the effectiveness of birth control pills.
  • Magnesium and zinc: These minerals do not interfere with the effectiveness of birth control but are important for overall hormonal balance.

It is well established1 that birth control pills deplete Vitamin C, E, magnesium, selenium, zinc, and B vitamins, such as folate, B6 and B12. This can lead to micronutrient deficiencies in certain individuals, which is why it is often recommended to take a prenatal or multivitamin if you are using the pill. 

What about herbs and other supplements, such as probiotics, fatty acids, and adaptogenic herbs—can these affect birth control? 

Let's take a look at how common supplements can impact hormones and the vitamins that affect birth control pills:

  • Omega-3s: Omega-3 fatty acids are essential fats that are beneficial for heart and brain health. There is no evidence suggesting that omega-3 supplements (such as Omega Plus) interact negatively with birth control pills. They are safe to take together and may even help manage some hormonal side effects associated with oral contraceptives or post-birth control syndrome due to their ability to manage inflammation.
  • Iron: Iron supplements do not affect how well birth control pills work. Iron is often added to birth control formulations or taken alongside them to help counteract the iron deficiency some women experience due to heavy menstrual bleeding.
  • Vitamin D: This essential nutrient helps absorb calcium and supports immune function and mental health. Vitamin D does not interfere with birth control's effectiveness. In fact, maintaining adequate vitamin D levels, such as by supplementing with vitamin D3, can support overall hormonal health, including when using birth control.
  • Vitex (Chaste Tree Berry): Vitex is an herb that's often used to help support estrogen and progesterone production. It is often used by those who experience PMS, PMDD, or menopause. While Vitex does influence hormone levels, there has not been research showing an interaction with birth control pills. Overall, it's considered safe to take Vitex, like what is found Balance Women's Hormone Support formula, while taking birth control—and in fact, it can help benefit women's hormones during reproductive years and during perimenopause. If you have specific concerns about this combination, consult with a healthcare provider before combining Vitex with hormonal contraceptives.
  • DIM (Diindolylmethane): DIM is a compound found in cruciferous vegetables and is sometimes used as a supplement for hormone balance. There is no current evidence to suggest that DIM affects birth control pills. However, due to its effects on hormone metabolism, at very high doses (600 mg and above) it could potentially lead to lower estrogen levels. Further consultation with a health professional is recommended if you plan to take doses exceeding 50-100 mg.
  • Calcium-D-Glucarate: This supplement supports natural liver and bowel detoxification of estrogen you no longer need. Similar to DIM, there is no strong evidence indicating a direct interaction with birth control effectiveness. Some experts suggest it may be helpful for those who are on the pill to help them effectively eliminate unnecessary estrogen from their system. 
  • DHEA: DHEA (dehydroepiandrosterone) is a hormone that can influence other hormone levels in the body, including those regulated by birth control pills. While there is no direct evidence to suggest that DHEA supplements significantly interfere with the effectiveness of birth control. Some research2 has suggested that women on oral contraceptive pills should supplement with DHEA in order to restore testosterone levels in the body. However, it's wise to consult with a healthcare provider before combining them due to potential hormonal fluctuations or side effects.
  • Magnesium: Magnesium plays a crucial role in hormone regulation, including estrogen metabolism, and also supports adrenal function and the HPA axis, which are the hormones that govern your stress response. Additionally, it's needed for hundreds of other reactions in the body, including those related to a normal stress response. Magnesium does not interact with birth control, and consuming enough can help you cope with stress better, deal with fewer mood swings, sleep more soundly, and assist in hormone balance. Consider taking magnesium glycinate (300 milligrams daily), the type found in Magnesium Plus formula, to improve your magnesium levels.
  • Probiotics: Probiotics will not interfere with birth control, but they do help to maintain a healthy gut microbiome, which is directly linked to hormone regulation. By supporting a healthy gut microbiome and estrobolome, Women's Probiotics can help the metabolism of estrogen precursors, leading to optimized estrogen levels. Probiotics can also help counteract birth control's effects on gut health, which can lead to various digestive systems.
  • St. John’s Wort: This herb is often used to support low moods, which can be a common side effect of birth control. However, St. John’s Wort is known to increase the enzyme activity3 in the liver that metabolizes hormones in birth control pills, potentially reducing their effectiveness4 and leading to unexpected pregnancy.

If you're interested in learning more about the best supplements to take for different hormonal issues, you can refer to these in-depth articles for help: 

What Medications Interfere with Birth Control Pills? 

what medications interfere with birth control pills

Certain medications can potentially interact with birth control pills5 by decreasing their effectiveness or increasing side effects. These include some antibiotics, anti-viral, and anticonvulsant drugs.

Examples of medications that may interact with birth control pills include:

Antibiotics

Some antibiotics, such as rifampin6 (and to a lesser extent, azithromycin erythromycin, ketoconazole, penicillin and derivatives, and tetracycline antibiotics), have been shown in some studies to reduce the effectiveness of birth control pills7 by increasing the breakdown of estrogen in the body. 

However, most common antibiotics like amoxicillin and doxycycline are generally not proven to have significant effects8 on birth control effectiveness, though caution is often advised, particularly when combining several antibiotics.

Which antibiotics affect birth control pills?

Rifampin has been shown to reduce estrogen levels in the blood, which may allow ovulation to occur, making birth control pills ineffective at preventing pregnancy.

Does amoxicillin interact with birth control?

It is less likely that amoxicillin with interact with your birth control pills, but it is important to discuss with your provider if you have concerns about avoiding pregnancy. 

Anti-seizure medications

Some drugs used for epilepsy and seizure (called anticonvulsants), such as phenobarbital, carbamazepine, and phenytoin, can possibly increase the metabolism of hormones9 in birth control pills, potentially decreasing their contraceptive effectiveness10.

HIV medications 

Some HIV medications, especially certain protease inhibitors and non-nucleoside reverse transcriptase inhibitors, can affect the levels of birth control hormones in the body, either increasing or decreasing their presence, which could impact their effectiveness.

Antifungal medications

Certain antifungal drugs, such as griseofulvin, can interact with birth control pills by affecting how hormones are processed in the liver.

Does Prednisone Interact with Birth Control?

Prednisone has not been found to affect birth control pills11. However, estrogen (found in the combination pill) can increase the action of prednisone and may make the steroids more potent.  

The bottom line: always inform your provider about all medications you're taking, including over-the-counter drugs and supplements, when discussing birth control options. You can also discuss potential interactions with a pharmacist before starting a new prescription. 

You can also consider using birth control alternatives, such as a condom or the copper IUD, while taking medications that are known to interact with hormonal birth control.

Does Taking Birth Control at Night Help to Reduce Side Effects?

does taking birth control at night help to reduce side effects

Taking birth control at night does not reduce its effectiveness, but it may help alleviate some side effects, such as nausea or headaches for some women.

There isn't an ideal time to take birth control; rather, what's most important is that it's taken consistently12, such as around the same time every day, and to avoid missing pills13.

That said, taking pills at night can potentially help manage birth control side effects by allowing the body to process hormones during sleep, reducing daytime side effects such as nausea or dizziness. 

Not all women experience side effects from birth control and do well when taking it any time of day, so timing is ultimately up to personal preference and tolerance.

Other FAQs about Taking Birth Control Pills

does ashwagandha interact with birth control

Can you take adaptogenic herbs (like Ashwagandha, Rhodiola, Maca, Shatavari, and Ginseng) with birth control?

It's usually safe to combine adaptogens and oral contraceptives. Ashwagandha and other adaptogenic herbs have not been shown to alter the effectiveness of birth control. These herbs can help you cope with stress and may impact cortisol levels, but they have not been shown to alter other hormone levels in a significant way.

Can any vitamins improve birth control's effects?

Birth control is already very effective (about 99% when taken properly). And no, there are no vitamins that have been proven to affect the effectiveness of birth control pills when taken at recommended dietary doses.

Should you avoid any foods or drinks when taking birth control?

Generally, no specific foods are known to interfere directly with the effectiveness of birth control pills. 

A balanced diet will not affect birth control. However, it's recommended to avoid large amounts of grapefruit juice14, which can possibly impact how your body absorbs different compounds, including hormones. 

Avoiding excessive alcohol is also smart because alcohol negatively affects digestion and detoxification, as well as general hormonal health.

And finally, while research hasn't shown that eating soy products will definitely affect birth control by altering hormone levels, it's best to eat soy in moderation to avoid any possible side effects (as soy has phytoestrogen effects which mimic those of estrogen).

Key Takeaways on Whether Birth Control Interacts With Supplements and Medications 

  • While most common vitamins and supplements do not interfere with the efficacy of birth control pills, it is important to discuss medications and supplements with your provider. It is also important to be aware that St. John’s Wort can affect your birth control pills effectiveness. 
  • There are several medications that can interfere with your birth control pills. It’s important to discuss this with your doctor before starting a new medication. 
  • Does taking birth control pills at night help reduce its effects (or potential side effects)? Timing does not alter birth control's effects. Some women find that taking birth control before bed can help reduce side effects such as nausea.
  • Always discuss any new supplements or medications with your healthcare provider to ensure your contraceptive remains effective, especially if you have a known hormonal imbalance and/or you're taking multiple supplements and medications at the same time.

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References

  1. https://pubmed.ncbi.nlm.nih.gov/23852908/ ↩︎
  2. https://pubmed.ncbi.nlm.nih.gov/27393080/ ↩︎
  3. https://pubmed.ncbi.nlm.nih.gov/15914127/ ↩︎
  4. https://www.goodrx.com/conditions/birth-control/can-medications-make-birth-control-less-effective ↩︎
  5. https://dmd.aspetjournals.org/content/51/6/718 ↩︎
  6. https://www.webmd.com/sex/birth-control/medicines-interfere-birth-control-pills ↩︎
  7. https://www.aafp.org/pubs/afp/issues/2019/1115/p599.html#:~:text=Antibiotics%20more%20likely%20to%20reduce,3 ↩︎
  8. https://www.drugs.com/article/antibiotics-and-birth-control.html ↩︎
  9. https://www.smsna.org/patients/blog/8-medications-that-can-interfere-with-your-birth-control-pills ↩︎
  10. https://www.sciencedirect.com/science/article/pii/S105913111500076X ↩︎
  11. https://www.nhs.uk/medicines/prednisolone/common-questions-about-prednisolone-tablets-and-liquid ↩︎
  12. https://www.mayoclinic.org/drugs-supplements/progestin-contraceptives-oral-route-parenteral-route/precautions/drg-20070184?p=1 ↩︎
  13. https://www.ncbi.nlm.nih.gov/books/NBK430882/ ↩︎
  14. https://www.goodrx.com/conditions/birth-control/supplements-that-interact-with-birth-control ↩︎
About The Author

Dr. Jolene Brighten

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Dr. Jolene Brighten, NMD, is a women’s hormone expert and prominent leader in women’s medicine. As a licensed naturopathic physician who is board certified in naturopathic endocrinology, she takes an integrative approach in her clinical practice. A fierce patient advocate and completely dedicated to uncovering the root cause of hormonal imbalances, Dr. Brighten empowers women worldwide to take control of their health and their hormones. She is the best selling author of Beyond the Pill and Healing Your Body Naturally After Childbirth. Dr. Brighten is an international speaker, clinical educator, medical advisor within the tech community, and considered a leading authority on women’s health. She is a member of the MindBodyGreen Collective and a faculty member for the American Academy of Anti Aging Medicine. Her work has been featured in the New York Post, Forbes, Cosmopolitan, Huffington Post, Bustle, The Guardian, Sports Illustrated, Elle, and ABC News. Read more about me here.