Endometriosis and hormones

How hormones can affect endometriosis and advice on how to treat and improve symptoms

• Endometriosis affects around one in ten women
• Hormones, oestrogen, progesterone and testosterone, can play important roles in endometriosis
• Various hormone treatments are available, as well as surgery for some women

Endometriosis is the second most common gynaecological condition after fibroids – it is estimated that two million women in the UK have endometriosis [1]. Yet it has been referred to as “the missed disease” [2], and there is still much to learn.

What is endometriosis?

The word endometriosis comes from the Greek words ‘endos’ (inside), ‘metra’ (womb) and ‘-osis’ (disease). With this in mind, endometriosis is a condition where tissue similar to the lining of your womb grows elsewhere in your body. This tissue can grow on your ovaries, fallopian tubes and around your bowel and bladder. It can also grow in other organs such as your lungs.

While some women with endometriosis do not experience symptoms, for others it can cause heavy, painful periods, pain in your abdomen, pelvis, and other organs, and for some women, problems with fertility. For women who have symptoms, there are many different treatments available to manage the condition and reduce the symptoms and associated pain.

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Some women who have endometriosis may also have adenomyosis – a condition where endometrial tissue grows into the muscular wall of your womb. Adenomyosis is more likely to cause heavy period bleeding than endometriosis.

RELATED: Adenomyosis and the perimenopause and menopause

How is endometriosis treated?

Treatment often varies between women. It can be effective and really improve symptoms.

Treatment may involve limiting or stopping the production of the hormone oestrogen. This is because oestrogen can encourage the tissue to grow, both those inside and outside of your womb. It is the presence of the cells elsewhere in the body that usually causes the unwanted symptoms.

There are different types of oestrogen and there is very little research about the effects of different oestrogens (such as oestradiol, oestrone and oestrogens in synthetic contraceptives) on endometriosis.

There are various treatments available, including hormones and painkillers. In more severe cases, or when those treatments have not improved symptoms, you may need surgery.

Surgery aims to remove or destroy the tissue found outside of your womb, known as endometriotic lesions or deposits. Keyhole surgery using a camera (laparoscope) inserted through small incisions in your abdomen is a common procedure used to destroy these endometrial deposits. In some cases an operation, such as a hysterectomy (removal of your womb) or removal of your ovaries is needed. Although these operations are often successful in improving endometriosis symptoms, they can lead to a surgical menopause occurring.

RELATED: Endometriosis and the menopause

Surgical menopause is when hormones (oestradiol, progesterone and testosterone) suddenly stop being produced in your body, due to such types of operations (or certain medications). It can cause a sudden onset of menopausal symptoms, which can be severe and disabling and have a negative impact on the quality of your life as well as your future health. Having the right type and dose of hormones is really important for women who have had a surgical menopause, and often improves menopausal symptoms considerably, as well as improving your health in the future.

RELATED: Surgical menopause and menopause in women with endometriosis

Can I have HRT and testosterone if I have or have had endometriosis?

If you have had an early surgical menopause (under the age of 45 years), it is very important that you consider taking hormones as without hormones you have a greater risk of developing conditions such as heart disease, osteoporosis and diabetes [3]. If you are perimenopausal or menopausal, or experiencing symptoms related to PMS or PMDD, then taking the right dose and type of hormones is likely to both improve your symptoms as well as your future health.

Replacement oestradiol comes in the form of a tablet, patch, gel or spray. The safest types are ones that are absorbed through your skin, as there is no risk of clot or stroke with these preparations. Natural progesterone is usually prescribed as an oral capsule but can also be used as a pessary for some women and testosterone is a cream or gel.

For the majority of women, the benefits of HRT outweigh any risks.

RELATED: HRT doses explained

Currently, there is a lack of high-quality research looking into the specific benefits and risks of HRT in women with endometriosis. There is a possibility that oestrogen can reactivate endometriosis, giving rise to symptoms of endometriosis occurring in a some women.

Oestradiol and oestrone work differently in your body so some women find that the synthetic oestrogen in contraceptives and some types of HRT can flare up and worsen their endometriosis whereas taking oestradiol in body identical HRT does not have these effects. Synthetic and natural hormones have very different effects in the body.

RELATED: Hormonal changes and endometriosis: busting myths and seeking help

Which types of HRT may I be offered?

If you naturally enter perimenopause or menopause (rather than due to medical or surgical intervention), you should be offered combined HRT – this contains both oestradiol and progesterone (or progestogen).

If you are thought to have some endometriosis remaining after a hysterectomy, for example around your bowel or bladder, you will usually be given progesterone with oestradiol, to reduce the risk of any endometriosis tissue being stimulated by the oestradiol. Women with endometriosis are usually given progesterone daily, which helps to reduce any symptoms and the chances of endometriosis recurring.

The safest type of progesterone is micronised progesterone or Cyclogest (progesterone pessary), which is body identical and derived from the yam plant and soy.

RELATED: Utrogestan (micronised progesterone) explained

Some women with endometriosis are prescribed a type of hormone-blocking drug, which is a GnRH analogue. This blocks hormones so leads to a chemical menopause. This can improve symptoms of endometriosis but lead to menopausal symptoms occurring, so it is often advisable to have add-back hormone replacement therapy – where HRT (sometimes with testosterone) is given at the same dose each day, which does not usually flare up endometriosis [4].

However, very occasionally endometriosis can reactivate spontaneously without taking any oestrogen. It is therefore important to report any recurrence of endometriosis symptoms such as pelvic pain, or bleeding from your vagina, bladder or bowel.

Taking testosterone can often really help improve your energy levels, mood, concentration and libido. Some women find that they have more benefits starting testosterone and progesterone before oestrogen. Both testosterone and progesterone can reduce inflammation so can be beneficial for some women. Testosterone does not stimulate the endometrium in the way that oestradiol does [5].

It is important for your dose and type of hormone treatment to be individualised for you.

RELATED: My story: endometriosis

Resources

ESHRE Endometriosis guideline

Endometriosis | Treatment summaries | BNF | NICE

References

1. UCLH Endometriosis Centre
2. Overton C., Park C. (2010), ‘Endometriosis. More on the missed disease’, BMJ, 341:c3727. doi: 10.1136/bmj.c3727
3. Langer, R. D. (2021), ‘The role of medications in successful aging’, Climacteric, 24(5), pp505–512. https://doi.org/10.1080/13697137.2021.1911991
4. Edmonds D.K. (1996), ‘Add-back therapy in the treatment of endometriosis: the European experience’, Br J Obstet Gynaecol. Oct;103 Suppl 14:10-3. PMID: 8916980.
5. Zang H., Sahlin L., Masironi B., Eriksson E., Lindén Hirschberg A. (2007), ‘Effects of testosterone treatment on endometrial proliferation in postmenopausal women’,  J Clin Endocrinol Metab, 92(6) pp2169-75. doi: 10.1210/jc.2006-2171.