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Deep infiltrating endometriosis: management by medical treatment versus early surgery: DIAMOND

What is DIAMOND?

DIAMOND is a research study to compare surgery with hormone treatment for women with deep endometriosis.

Endometriosis is a common condition affecting 1 in 10 women, which can cause severe pain. It happens when cells similar to those lining the womb grow outside it, generally on surfaces and organs within the pelvic cavity, causing bleeding, scarring and inflammation. Occasionally, rather than growing on or very near the surface, the endometriosis cells can grow deeper into tissues and organs, such as the bowel, bladder and the vagina causing a painful condition which used to be known as “deep infiltrating endometriosis” and is now called deep endometriosis (DE).

DE is treated in one of two ways:
• by taking hormones which shrink areas of endometriosis by preventing abnormal cells from growing
• by using keyhole (laparoscopic) surgery to remove areas of endometriosis

Each treatment has its own benefits and potential drawbacks. Hormones can produce side effects and are not suitable for women who want to get pregnant. They may also not provide sufficient pain relief in some women who may need to have surgery. Keyhole surgery for DE can reduce pain in many women, but the procedure is complex with a risk of damage to surrounding organs like blood vessels, bowel and the bladder.

Women who consent to participate in DIAMOND will receive either surgery or hormone treatment for 18 months. We will keep in touch with participants for up to 18 months to see how they have been getting on.
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Can I take part?

We are recruiting women in the UK aged 18-49 seeking treatment for pain with confirmed deep endometriosis and suitable for either surgical or medical management and able and willing to give informed consent to participate.


If you are interested in taking part, or have any questions

Where can I take part?

NHS Grampian Aberdeen

Key people:


  • Prof Kevin Cooper


Birmingham Women and Children's NHS

Key people:


  • Prof Justin Clark


Steelhouse Lane
B4 6NH

Study news



Trial sites

Latest addition to sites:

Birmingham Women and Children's NHS
NHS Grampian Aberdeen

Key facts about the study and documents

What is this study about?

If you are eligible, would like to take part and your local hospital is a study site, they will send you information about the DIAMOND study.

To take part you will be asked to sign a consent form and asked some questions about your health and your endometriosis symptoms. After this you will be randomised to receive either:
• Surgery (with or without neoadjuvants or analgesics)
• Hormone treatment (with or without neuromodulator or analgesics)

Whichever group you are in, you will continue to receive NHS care.

We will follow you up in the study for 18 months using by sending questionnaires for you to complete at home.

There is an extra part of the study that is optional. In this extra part, we will ask some participants to take part in an interview. If you agree to take part in the DIAMOND study, we will ask you whether or not you would like to receive information about these interviews and to be contacted by the interview team.

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You can find out more information about DIAMOND here:

Download documents:

Key contacts

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Key questions & answers

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Funding acknowledgement

This project was funded by the National Institute for Health Research Health Technology Assessment (HTA) programme (reference NIHR130310) and is run by the University of Aberdeen and NHS Grampian. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

General Data Protection Regulation (GDPR)

Participant Information

University of Aberdeen/NHS Grampian is the sponsor for this study based in the United Kingdom. We will be using information from you and your medical records in order to undertake this study and will act as the data controller for this study. This means that we are responsible for looking after your information and using it properly. University of Aberdeen/NHS Grampian will keep identifiable information about you at least 10 years after the study has finished.

Your rights to access, change or move your information are limited, as we need to manage your information in specific ways in order for the research to be reliable and accurate. If you withdraw from the study, we will keep the information about you that we have already obtained. To safeguard your rights, we will use the minimum personally-identifiable information possible.

You can find out more about how we use your information here : or by contacting the Data Protection office at