Estrogen Dominance and Fertility

By Halle Tecco, MBA, MPH

You’ve probably heard of estrogen, an essential hormone that plays a role in the menstrual cycle, pregnancy, and overall reproductive health. Estrogen levels fluctuate throughout your cycle and your life stages. It works together with another sex hormone called progesterone, to keep things in balance. But when estrogen is chronically too high relative to progesterone, it can lead to a condition known as estrogen dominance (or unopposed estrogen). In this article, we will explore what estrogen dominance is, what causes it, how it can impact fertility, and ways to help regulate hormones for optimal reproductive health. [1,2,3]

What is Estrogen Dominance?

The ovaries produce estrogen and progesterone, which are the predominant female sex hormones. [4] Estrogen dominance is when there is an excess of estrogen in the body in relation to progesterone. [1]  

The state of estrogen dominance can arise for a couple of reasons including excessive production of estrogen or underproduction of progesterone, changes in estrogen metabolism and excretion, or a general imbalance between the levels of estrogen and progesterone. [1] Some people are genetically predisposed to have estrogen dominance, and for other people, it occurs for other reasons. [5] 

Estrogen dominance is thought to be associated with breast and uterine cancers, fibroids, endometriosis, autoimmune diseases, polycystic ovarian syndrome (PCOS), and infertility. [1-2] 

What Causes Estrogen Dominance?

There are several causes of elevated estrogen levels in women. Your body may be making too much estrogen, you may be getting too much estrogen from other sources, like medication, or your body may be having issues breaking down and removing the estrogen from your body. [6-7] Here are some potential reasons this could be happening [4,7-10]: 

• Medications: Some medications can impact estrogen levels.
• High BMI: Since fat tissues release estrogen, increased body fat can lead to high estrogen.
• Stress: Stress also impacts your estrogen levels through cortisol. Cortisol is produced as a response to stress. A high cortisol level limits your body from making enough progesterone to balance estrogen levels.
• Alcohol: Alcohol can raise estrogen levels and inhibit estrogen from being broken down.
• Exposure to endocrine-disrupting chemicals: Estrogen-like endocrine-disrupting chemicals (EEDC) are man-made chemicals that alter the functions of the endocrine system and cause various health defects by interfering with estrogen. Unfortunately today, EEDCs are everywhere in our environment and the products we use, including plastics, pesticides, and personal care products. [9] Look out for these ingredients in products you are using [9]: 

• Dichlorodiphenyltrichloroethane (DDT)
• Dioxin
• Polychlorinated biphenyls (PCBs)
• Bisphenol A (BPA)
• Polybrominated biphenyls (PBB)
• Phthalate esters
• Endosulfan
• Atrazine
• Aeranol

Read more in Chemicals to Avoid While Pregnant

• Poor liver function: Another factor that can contribute to estrogen dominance is poor liver function. The liver, the second largest organ in the body, is responsible for metabolizing and eliminating excess sex hormones from the body. If the liver is not doing its job, it can lead to an accumulation of estrogen in the body.

How do High Estrogen Levels Impact Fertility?

Abnormal estrogen levels can lead to infertility or difficulty conceiving, so you may want to test your hormone levels if you’ve been trying to conceive for some time with no success. [1-2]  If estrogen levels are to blame, you and your healthcare provider can develop a treatment plan to help restore hormone levels. 

What About High Estrogen in Men?

Estradiol plays an extensive role in overall male health and reproductive function. [11] In cis men, estradiol modulates sex drive, supports regular erectile function, and regulates healthy spermatogenesis (the production of sperm). [11] 

Outside of the reproductive system, estradiol has numerous applications and functions, including [12]:

• Maintaining bone health
• Regulating the balance of lean muscle mass and fat mass
• Supporting regular brain function
• Metabolizing lipids (fats and fatty acids)

Estradiol is a necessary hormone used in the production of sperm within the testes. However, excessively high estrogen levels can slow down sperm production, affect sperm quality or motility, or cease sperm production entirely. [13] 

In addition, getting and maintaining an erection requires a fragile balance of testosterone and estrogen. An elevated estrogen level can tip this balance, resulting in erectile dysfunction. This can be even more prominent if you also have reduced testosterone levels. [11,13] 

What is a Normal Estrogen Level for Men and Women?

Estradiol (E2) is one of the main types of estrogens, which can be tested through blood or urine.  According to Mayo Medical Laboratories, the following estradiol levels are considered normal [14]:

• Premenopausal adult females: 15-350 pg/mL (varies throughout the menstrual cycle)
• Postmenopausal adult females: <10 pg/mL
• Adult males: 10-40 pg/mL

When you take a hormone test, each lab must define its own reference range for each type of test since collection kit materials, chemicals used to perform testing, lab instruments, and more can vary from lab to lab. When you receive your result, they should come with this reference range showing where your numbers fall. This is a normal part of the lab testing process—so it’s best to interpret your estradiol test results using the reference ranges provided by the laboratory used for testing.

How Can I Check My Hormone Levels at Home?

You can request hormone tests to gain insight into estrogen levels through a healthcare provider—but these days, it’s far from the only option. You can check estrogen levels at home by testing the blood, urine, or saliva [15]: 

• Blood tests. At-home estrogen blood tests are quick and easy. You just need to prick your finger and collect a small blood sample in a vial. After that, you can send your sample to a lab for testing.
• Urine tests. Estrogen tests that use urine take a little longer to administer. That’s because you need to take samples of the urine throughout a 24-hour period. To administer one of these tests, you must collect a small sample of urine every time you empty your bladder and store the samples in a refrigerator. Once you’re finished, you can send the samples to the lab.
• Saliva tests. Lastly, you can collect a saliva sample to check your estrogen levels. Like urine tests, estrogen saliva tests typically need to be administered multiple times within one day to provide accurate results. All you need to do is spit into a test tube according to the schedule laid out by your healthcare provider.

Testing estrogen levels at home is a straightforward process. You don’t need to do anything special to prepare for your test. If you opt for a blood test, the entire process shouldn't take more than a few minutes.

Shop At-Home Hormone Tests

Ways to Maintain Normal Estrogen Levels

Maintaining normal estrogen levels is essential for optimal health and fertility in both men and women, for all the reasons discussed above. Fortunately, there are several ways to help keep estrogen levels in check:

• Medications: If you’re taking medications that are giving you high estrogen levels, your healthcare provider may want to adjust your prescription. [7] There are also drugs you can take that stop estrogen production and release to help keep levels normal. Of course, you should never stop or start taking any drugs without the guidance of your personal healthcare provider.
• Lifestyle changes: You can lower your estrogen levels by reducing your body fat, relieving stress, limiting alcohol, eating healthy, and when possible, decreasing exposure to xenoestrogens, also known as “foreign” estrogens. [6-7] Foreign estrogens are found in products such as cigarette smoke, car exhaust, cosmetic products, and even some food sources. [16] 

Next Steps

Estrogen dominance can have various negative impacts on reproductive health, including infertility, for both men and women. There are many factors that can cause high estrogen levels, including medications, stress, exposure to endocrine disrupting chemicals, and poor liver function. 

If you suspect that you may have estrogen dominance, you can have your levels tested through the Natalist Fertility Test (for women) or the Everlywell Men’s Health Test (for men).  

Taking steps to optimize reproductive health by balancing hormones can lead to better fertility and overall well-being. We wish you all the best on your journey!

Sources:

1. Kolan A. Estrogen Dominance. Whole Health Library. US Department of Veterans Affairs. 2014. Accessed May 2023. URL
2. Patel S, Homaei A, Raju AB, Meher BR. Estrogen: The necessary evil for human health, and ways to tame it. Biomed Pharmacother. 2018;102:403-411. doi:10.1016/j.biopha.2018.03.078
3. Özdemir AZ, Karli P, Gülümser Ç. Does high estrogen level negatively affect pregnancy success in frozen embryo transfer?. Arch Med Sci. 2020;18(3):647-651. Published 2020 Jan 29. doi:10.5114/aoms.2020.92466
4. Palmisano BT, Zhu L, Stafford JM. Role of Estrogens in the Regulation of Liver Lipid Metabolism. Adv Exp Med Biol. 2017;1043:227-256. doi:10.1007/978-3-319-70178-3_12
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6. Estrogen. Cleveland Clinic. URL. Updated February 2, 2022. Accessed February 28, 2023.
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9. Roy JR, Chakraborty S, Chakraborty TR. Estrogen-like endocrine disrupting chemicals affecting puberty in humans--a review. Med Sci Monit. 2009;15(6):RA137-RA145.
10. Schaub NA. Hautveränderungen bei Lebererkrankungen [Skin changes in liver diseases]. Praxis (Bern 1994). 2002;91(23):1037-1041. doi:10.1024/0369-8394.91.23.1037
11. Chen T, Wu F, Wang X, et al. Different levels of estradiol are correlated with sexual dysfunction in adult men. Sci Rep. 2020;10(1):12660. Published 2020 Jul 29. doi:10.1038/s41598-020-69712-6
12. Estradiol. Science Direct. URL. Accessed May 2023. 
13. Chen HR, Tian RH, Li P, Chen HX, Xia SJ, Li Z. Estradiol is an independent risk factor for organic erectile dysfunction in eugonadal young men. Asian J Androl. 2020;22(6):636-641. doi:10.4103/aja.aja_135_19
14. Estradiol, Serum. TEST ID: EEST. Mayo Clinic Laboratories. Accessed May 2023. URL
15. Estrogen Levels Test. MedlinePlus. Accessed May 2023. URL.
16. Fucic, A., Gamulin, M., Ferencic, Z. et al. Environmental exposure to xenoestrogens and oestrogen related cancers: reproductive system, breast, lung, kidney, pancreas, and brain. Environ Health 11 (Suppl 1), S8 (2012). https://doi.org/10.1186/1476-069X-11-S1-S8