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9 Biomarkers Birth Control Affects: Understand Your Blood Test Results

Don't be left in the dark. Explore the hormonal effects of birth control on your blood test results. Learn how to make informed choices for a balanced and healthy cycle.

Ashley Reaver
By Ashley Reaver
Jovan Mijailovic
Edited by Jovan Mijailovic

Updated April 19, 2024.

A woman looking at birth control pills.

At InsideTracker, users often ask us if hormonal contraceptives can affect female biomarkers. The answer? Yes. Like any other medication, they can interfere with different pathways and processes in the body.

Naturally, there can be unintended residual effects, like nudging some blood biomarkers outside of the normal reference range. Some of these changes may be due to contraceptive use, while others can be the result of a combination of factors.

Understanding your biomarkers is key to living healthier, longer. So, let's explore how hormonal birth control impacts them.



Key takeaways

  • Oral contraceptives can lower DHEAS, Vitamin B12, and testosterone. They may also elevate SHBG and cortisol. These hormonal changes may affect energy levels, muscle and bone health, sex drive, and inflammation.
  • Combination contraceptives like the pill and patch may increase HDL (good) cholesterol and triglycerides, while progestin-only options may decrease HDL.
  • Hormonal birth control suppresses estradiol and progesterone, which is reflected in lower blood levels during the menstrual cycle.
  • Not all hormonal contraceptives affect biomarkers in the same way. The pill and patch have different effects compared to implants or injections.


1. Dehydroepiandrosterone-sulfate (DHEAS)

DHEAS levels in blood tests are significantly lower for oral contraceptive pill (OC) users. The hormone is essential for energy, muscle and bone health, and sexual function for men and women. [1,2] The body synthesizes this molecule into estradiol and testosterone.

OC reduces DHEAS by suppressing androgens made by the adrenal glands. It can also cause them to produce more cortisol, which can further lower the levels of the hormone.

DHEAS begins to drop soon after beginning OC. Depending on the duration of use, it can take a while for the levels to rise once you stop using OC.

Note: OC is the only form of a hormonal contraceptive with evidence to suggest a relationship to lower DHEAS. The hormone's levels also naturally decline after the mid-20s. [1,2]

A bar chart showing the affect of birth control on DHEAS.


» Find out how DHEAS signals aging in women

2. Sex hormone binding globulin (SHBG)

Birth control that combines estrogen and progesterone—OC, patch, vaginal ring— can affect the levels of SHBG in your blood test results. [2,3] This hormone binds to testosterone, reducing its bioavailability.

The influx of exogenous estrogens from birth control also causes the liver to increase dose-related production of SHBG. You can reach peak levels in as little as three weeks after beginning OC use, and return to normal just as quickly after you stop taking it.

Since increases in SHBG are dose-dependent, OC forms with lower amounts of synthetic estrogens result in the least increase in SHBG. On the other hand, more potent ones—like the patch and the ring—cause a bigger rise.

Note: Progestin-only contraceptives like the IUD, implant, and injection don't correlate with an increase in SHBG.

A chart displaying OC effect on SHBG


3. Estradiol

Estradiol fluctuates naturally throughout a woman’s monthly menstrual cycle. It's normal for it to be low during the first half of the cycle—the follicular phase. During ovulation and the second half—the luteal stage—the levels can be much higher.

Use of any birth control can blunt the changes in estradiol over the course of a cycle, affecting blood test results. It's common for women using contraceptives to have lower than expected levels, especially during the luteal phase. [4-6]

InsideTracker's Ultimate plan shows optimal zones for estradiol while considering contraceptive use. The results show you if your levels are optimized for you, or if they could still use improvement.




4. Testosterone

Birth control typically suppresses testosterone production by up to 50%. [2] Researchers think this decrease happens because it subdues the testosterone created in the ovaries and adrenal glands. They also link it to increased SHBG levels in blood test results.

Note: Testosterone is important, and not just for men. Women also need testosterone for energy, muscle and bone health, and a healthy libido.

A chart displaying OC effect on testosterone.


» Check out different markers associated with female fertility

5. Cortisol

Birth control may affect cortisol blood test results, causing it to be higher. [2] OC suppresses the production of androgens—like testosterone—from the adrenal glands. That's why the body may produce more cortisol to funnel the chemical byproducts that would otherwise go toward making androgens.

This relationship occurs only in women who use OCs, not in any other forms of hormonal contraceptives. Those with elevated cortisol levels should also consider increasing sleep, reducing stress, trying meditation, and eating enough calories.

A chart displaying OC effect on cortisol.


6. Progesterone

Progesterone increases dramatically in the second half of the menstrual cycle in response to ovulation. Hormonal contraceptives can prevent this rise, leading to lower levels in your blood test results during the luteal phase.

Like with estradiol, the InsideTracker Ultimate plan considers your birth control use when calculating optimal zones. So, while your levels may be lower than in those not using them, the blood test results will show you're optimized. [7,8]




7. hsCRP

Estrogen-containing birth control also affects your blood test results by elevating hsCRP. [9] It may predispose individuals to a higher inflammatory response to physical activity, especially in athletes. [10]

A concerted effort to combat inflammation with a diet high in antioxidants like vitamins A, C, and E may mitigate any resulting damage. A diet rich in healthy fats and adequate sleep can also help.

A chart displaying the effect of OCs on hsCRP.


» Learn to track your body's data for better health outcomes

8. Vitamin B12

Vitamin B12 is a critical nutrient due to its role in DNA and red blood cell synthesis. It also affects lipid and carbohydrate metabolism, and brain and nervous system function. The levels fluctuate throughout the female lifespan, but it's especially important for those in their reproductive years.

Birth control may affect your vitamin B12 blood results by making ti show up lower than usual—even when controlling for intake through diet. [11,12] Researchers aren't sure whether contraceptive use results in a disruption of vitamin B12 absorption, recycling, or storage.

Note: If you have lower vitamin B12 and are taking oral contraceptives, focus on increasing your intake. Focus on foods like meat, eggs, and dairy while monitoring your levels. 

A chart displaying effects of OCs on Vitamin B12.


9. Cholesterol

Birth control has been shown to affect cholesterol markers in blood tests, like triglycerides, LDL and HDL. Different forms can move them in different directions.

For example, combined contraceptives like the pill and the patch may increase HDL cholesterol. On the other hand, the progestin-only contraceptive implant and injection relate to lower levels. [13–15]

Pill and patch birth control may increase triglycerides, and most hormonal contraceptives don't impact LDL cholesterol. But, evidence suggests that the implant may have a protective, lowering effect on LDL levels in your blood test results. [13]

Manage your hormones for optimal health

Hormonal birth control can affect certain blood test results. By understanding how these contraceptives might impact biomarkers like DHEA-S, cortisol, and SHBG, you can interpret your blood work more accurately alongside your doctor.

InsideTracker can also help you identify and monitor any effects that your birth control may have on your biomarkers, including all the one’s discussed here. You also receive food, supplement, and lifestyle recommendations to help optimize them.

Understanding the various impacts of the different forms can be useful when prioritizing your own biomarkers and when talking with your physician about what contraceptive is right for you.

Disclaimer: InsideTracker doesn't treat or diagnose medical conditions. Consult your physician for any health concerns.




References:

[1] “Effect of low-dose oral contraceptive on gonadotropins, androgens, and sex hormone binding globulin in nonhirsute women,” PubMed, Jan. 01, 1990. Available: https://pubmed.ncbi.nlm.nih.gov/2136834/

[2] Y. Zimmerman, E. Mj, C. B. Hj, M. A. Blankenstein, and F. Bc, “The effect of combined oral contraception on testosterone levels in healthy women: a systematic review and meta-analysis,” Human Reproduction Update, vol. 20, no. 1, pp. 76–105, Sep. 2013, doi: 10.1093/humupd/dmt038. Available: https://pubmed.ncbi.nlm.nih.gov/24082040/

[3] M. Raps et al., “Sex hormone‐binding globulin as a marker for the thrombotic risk of hormonal contraceptives,” Journal of Thrombosis and Haemostasis, vol. 10, no. 6, pp. 992–997, Jun. 2012, doi: 10.1111/j.1538-7836.2012.04720.x. Available: https://pubmed.ncbi.nlm.nih.gov/22469296/

[4] R. Stricker, R. Eberhart, M.-C. Chevailler, F. A. Quinn, P. Bischof, and R. Stricker, “Establishment of detailed reference values for luteinizing hormone, follicle stimulating hormone, estradiol, and progesterone during different phases of the menstrual cycle on the Abbott ARCHITECT® analyzer,” Clinical Chemistry and Laboratory Medicine, vol. 44, no. 7, Jan. 2006, doi: 10.1515/cclm.2006.160. Available: https://pubmed.ncbi.nlm.nih.gov/16776638/

[5] D. R. Mishell, I. H. Thorneycroft, R. M. Nakamura, Y. Nagata, and S. Stone, “Serum estradiol in women ingesting combination oral contraceptive steroids,” American Journal of Obstetrics and Gynecology, vol. 114, no. 7, pp. 923–928, Dec. 1972, doi: 10.1016/0002-9378(72)90098-1. Available: https://pubmed.ncbi.nlm.nih.gov/4645131/

[6] P. D. Darney, R. N. Taylor, C. Klaisle, K. Bottles, and C. Zaloudek, “Serum concentrations of estradiol, progesterone, and levonorgestrel are not determinants of endometrial histology or abnormal bleeding in long-term Norplant® implant users,” Contraception, vol. 53, no. 2, pp. 97–100, Feb. 1996, doi: 10.1016/0010-7824(95)00266-9. Available: https://pubmed.ncbi.nlm.nih.gov/8838486/

[7] “Acute effect of alcohol on estradiol, estrone, progesterone, prolactin, cortisol, and luteinizing hormone in premenopausal women,” PubMed, Jun. 01, 1999. Available: https://pubmed.ncbi.nlm.nih.gov/10397281/

[8] P. D. Darney, R. N. Taylor, C. Klaisle, K. Bottles, and C. Zaloudek, “Serum concentrations of estradiol, progesterone, and levonorgestrel are not determinants of endometrial histology or abnormal bleeding in long-term Norplant® implant users,” Contraception, vol. 53, no. 2, pp. 97–100, Feb. 1996, doi: 10.1016/0010-7824(95)00266-9. Available: https://pubmed.ncbi.nlm.nih.gov/8838486/

[9] C. J. Sørensen et al., “Combined Oral Contraception and Obesity Are Strong Predictors of Low-Grade Inflammation in Healthy Individuals: Results from the Danish Blood Donor Study (DBDS),” PloS One, vol. 9, no. 2, p. e88196, Feb. 2014, doi: 10.1371/journal.pone.0088196. Available: https://pubmed.ncbi.nlm.nih.gov/24516611/

[10] S. Cauci, M. P. Francescato, and F. Curcio, “Combined oral contraceptives increase High-Sensitivity C-Reactive protein but not haptoglobin in female athletes,” Sports Medicine, vol. 47, no. 1, pp. 175–185, Apr. 2016, doi: 10.1007/s40279-016-0534-9. Available: https://pubmed.ncbi.nlm.nih.gov/27084393/

[11] J. O. McArthur, H. Tang, P. Petocz, and S. Samman, “Biological variability and impact of oral contraceptives on vitamins B6, B12 and folate status in women of reproductive age,” Nutrients, vol. 5, no. 9, pp. 3634–3645, Sep. 2013, doi: 10.3390/nu5093634. Available: https://pubmed.ncbi.nlm.nih.gov/24067390/

[12] A. B. Berenson and M. Rahman, “Effect of hormonal contraceptives on vitamin B12 level and the association of the latter with bone mineral density,” Contraception, vol. 86, no. 5, pp. 481–487, Nov. 2012, doi: 10.1016/j.contraception.2012.02.015. Available: https://pubmed.ncbi.nlm.nih.gov/22464408/

[13] A. B. Berenson, M. Rahman, and G. S. Wilkinson, “Effect of injectable and oral contraceptives on serum lipids,” Obstetrics and Gynecology (New York. 1953. Online)/Obstetrics and Gynecology, vol. 114, no. 4, pp. 786–794, Oct. 2009, doi: 10.1097/aog.0b013e3181b76bea. Available: https://pubmed.ncbi.nlm.nih.gov/19888036/

[14] T. Piltonen et al., “Oral, transdermal and vaginal combined contraceptives induce an increase in markers of chronic inflammation and impair insulin sensitivity in young healthy normal-weight women: a randomized study,” Human Reproduction, vol. 27, no. 10, pp. 3046–3056, Jul. 2012, doi: 10.1093/humrep/des225. Available: https://pubmed.ncbi.nlm.nih.gov/22811306/

[15] G. S. Merki‐Feld, B. Imthurn, M. Rosselli, and K. Spanaus, “Implanon use lowers plasma concentrations of high-molecular-weight adiponectin,” Fertility and Sterility, vol. 95, no. 1, pp. 23–27, Jan. 2011, doi: 10.1016/j.fertnstert.2010.05.018. Available: https://pubmed.ncbi.nlm.nih.gov/20576266/