CERM: Can doxycycline prevent miscarriage in women with endometritis?

Researchers funded by Tommy’s are taking part in a large clinical trial to find out whether treatment with an antibiotic called doxycycline can prevent further losses in women with a condition called endometritis who have already had two or more miscarriages.
  • Author's list

    Professor Siobhan Quenby, Professor Jan Brosens, Professor Arri Coomarasamy, external collaborators

    Start date: 2018
    End date: 2022

Why do we need this research?

Endometritis is a condition in which the lining of the womb – or the endometrium – becomes inflamed. In some women, this can cause symptoms such as bleeding and pain, while other women may have no symptoms at all; these women may not even realise they have endometritis. 

Researchers think that women with endometritis are more likely to have a miscarriage. A healthy womb lining is important for the embryo to be able to attach to the womb properly, and it is thought that endometritis can disrupt this process. As endometritis is likely caused by an imbalance in the bacteria that are present in the vagina, cervix, womb, fallopian tubes and ovaries, the standard treatment is an antibiotic called doxycycline. In the USA and parts of Europe, doxycycline is also used to treat women who have had two or more miscarriages in a row – known as recurrent miscarriage – but this treatment has not been thoroughly tested.

What’s happening in this project?

Researchers funded by Tommy’s are working with other scientists from around the UK to find out for certain whether doxycycline treatment can prevent miscarriage in women with endometritis. To do this, they are carrying out the ‘Chronic Endometritis and Recurrent Miscarriage’ trial – or CERM – which will involve 3,000 women who have experienced recurrent miscarriage. The researchers will take a sample of the womb lining from each woman to find out whether they have endometritis, and if they do, they will be given either a 14-day course of doxycycline or placebo. Once the treatment is complete, the women will be advised to start trying to conceive.

To find out if treatment with doxycycline is successful, the research team will look to see how many women are still pregnant at 12 weeks and how many have live births. They will also take swabs of the vagina, cervix and womb lining to find out more about how doxycycline treatment affects the mixture of bacteria that can be found in these places.

What difference will this project make?

Around half of women who have had two or more miscarriages in a row are estimated to have endometritis. If doxycycline treatment is shown to reduce the chances of miscarriage in these women, it is likely to be introduced as the standard treatment in hospitals around the UK. This has the potential to dramatically reduce the number of women who have to suffer the pain of yet another miscarriage.