This information is for women who have pain caused by endometriosis. It tells you about contraceptive pills, a treatment used for endometriosis. It is based on the best and most up-to-date research.
Do they work?
Yes. Contraceptive pills can help with the pain of endometriosis.
Unlike other hormone treatments, you don't have to stop taking the pill after six months. This could be important, as pain often returns when you stop treatment. Contraceptive pills also have fewer unpleasant side effects than other hormone treatments.
What are they?
The pill is normally taken to prevent an unwanted pregnancy. But some women take it to relieve pain during their periods. And it can help with other pain caused by endometriosis.
If you don't want to get pregnant, your doctor may suggest you try the pill to relieve your pain. If it works, you might not need to have a laparoscopy to find out for certain whether you have endometriosis.
There are two types of contraceptive pills: combined contraceptive pills and progestogen-only contraceptive pills. Both types seem to work well at relieving pain in endometriosis. 
Combined contraceptive pills contain:
Progestogen-only pills just contain a progestogen.
You take one pill each day for three weeks, then have a week off (or take dummy pills for a week). During the week off, you have a period. It's usually lighter and shorter than your normal period. For some kinds of contraceptive pills, you don't need to have the week off. If you don't have a week off every month, your periods stop completely.
There are many different contraceptive pills. They contain different kinds of oestrogen and progestogen, at slightly different doses. The table shows some common brands (with the types of oestrogen and progestogen they contain). 
|Brand name||Type of oestrogen||Type of progestogen|
Your doctor will help you find a pill that suits you.
How can they help?
Endometriosis can cause pain in the area between your hips (your pelvis). The pill reduces pain in this area.
It works for all kinds of pain, including painful periods, continuous pain, and pain during or after sex. In one study, more than half the women taking the pill got rid of their pain completely.   
The pill might not work as well as hormone treatments called GnRH analogues at reducing pain linked with endometriosis.  
How do they work?
The pill either contains oestrogen and progestogen hormones, or just a progestogen.
These hormones stop your brain producing two other hormones called luteinising hormone (LH) and follicle-stimulating hormone (FSH). LH and FSH make your ovaries work. This is part of your monthly cycle.
If you're taking the pill, your ovaries don't produce eggs or hormones of their own. So the lining of your womb stays thin, and your periods are lighter.  And any patches of endometriosis will shrink, bleed less, and hurt less.