The aim of hormone treatments is to limit or stop the production of oestrogen in your body.
This is because oestrogen encourages endometriosis to grow and shed. Without exposure to oestrogen, the endometriosis tissue can be reduced, which helps to ease your symptoms. However, hormone treatment has no effect on adhesions (‘sticky’ areas of endometriosis, which can cause organs to fuse together) and cannot improve fertility.
Hormone treatments stop the production of oestrogen by putting you in either an artificial state of pregnancy or an artificial state of menopause, which stops your periods.
Once your periods have stopped, the endometriosis is no longer aggravated. However, it is important to note that some of these treatments are not contraceptives.
There are four broad types of hormone-based treatment:
- the combined oral contraceptive pill
- gonadotrophin-releasing hormone (GnRH) analogues
Progestogens are synthetic hormones that behave like the natural hormone progesterone. They stop eggs from being released (ovulation), which can help to shrink endometriosis tissue. However, they can have side effects such as bloating, mood changes, irregular bleeding and weight gain.
Drug names include Norethisterone, Medroxyprogesterone Acetate and Dydrogesterone
The Mirena intrauterine system, a T-shaped contraceptive device that fits into the womb and releases progestogen, has been successfully used for the treatment of endometriosis.
The combined oral contraceptive pill
The combined contraceptive pill contains the hormones oestrogen and progestogen. Although it is not officially licensed for the treatment of endometriosis, the pill can help relieve milder symptoms and can be taken over long periods of time. It stops the function of the ovaries, which in turn stops the menstrual cycle.
The pill can have side effects, but you can try different brands until you find one that suits you.
Gonadotrophin-releasing hormone (GnRH) analogues
GnRH analogues are synthetic hormones that cause an artificial menopause. They are taken as a nasal spray, implant or injection and work in a similar way to gonadotrophin-releasing hormone (a natural female hormone).
When you take GnRH analogues continuously for more than two weeks the production of oestrogen is stopped. They often have side effects such as hot flushes, vaginal dryness and low libido, so they are recommended alongside hormone replacement therapy (HRT), which is usually used to reduce the symptoms of menopause.
Drug names include Zoladex (Goserelin), Buserelin and Leuprorelin.
Also known as testosterone derivatives, antiprogestogens are synthetic hormones that bring on an artificial menopause by decreasing the production of oestrogen and progesterone. Side effects can include weight gain, acne, mood changes and the development of masculine features (hair growth and deepening voice).
Drug names include Danazol and Gestrinone.