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Trial of new test and treatment could benefit half of women with recurrent miscarriage

● Potential new test and new treatment for reducing recurrent miscarriage

● First clinical trial of commonly used antibiotic for preventing miscarriage to be conducted at University of Warwick in partnership with University Hospitals Coventry and Warwickshire NHS Trust.

● Up to half of women with recurrent miscarriage, about 7000 couples in England and Wales per year could benefit

● Research launched at the British Science Festival today (12 September)

A major new clinical trial at the University of Warwick in partnership with University Hospitals Coventry and Warwickshire NHS Trust will investigate whether a course of antibiotics prior to conceiving could reduce the likelihood of miscarriage in up to 50% of cases.

Researchers at the University of Warwick Clinical Trials Unit are leading the Chronic Endometritis and Recurrent Miscarriage (CERM) trial, which aims to discover whether using the antibiotic doxycycline in women with the condition endometritis can improve their chances of having a baby and treat recurrent miscarriage by improving the balance of bacteria present in their reproductive system.

The trial has received £1.9 million funding from the Efficacy and Mechanism Evaluation (EME) Programme – an MRC and NIHR partnership - and will involve over 3,000 women in NHS hospitals in the United Kingdom who have recurrent miscarriage. It is launched today (12 September) at the British Science Festival, this year held in partnership with the University of Warwick.

In some women the lining of the womb (the endometrium) is inflamed, a condition called endometritis, and researchers have found a link between this and miscarriage. Some women will experience symptoms such as bleeding and pain, and it is commonly treated using an antibiotic called doxycycline. However, some women exhibit no obvious symptoms from endometritis and there is currently no standard screening test for the condition for those who have experienced miscarriage.

Not everyone who has recurrent miscarriage has endometritis so, using a test for endometritis optimised by scientists at Warwick Medical School, the researchers will first identify women with the condition. To find out if doxycycline can reduce miscarriage and increase the number births in women who have experienced two or more early miscarriages, the researchers will carry out a double blind randomised controlled trial, by comparing a 14-day course of doxycycline against a placebo. Women will be advised to start trying to conceive once they have finished the course.

Doxycycline is a common antibiotic prescribed for a number of bacterial infections, such as chest infections. Treatment for recurrent miscarriage using doxycycline is currently available in some European countries and the USA, but this will be the first time that the womb lining test and treatment will be thoroughly tested in a clinical trial.

Warwick Medical School’s Professor Siobhan Quenby, Principal Investigator on the trial, said: “This is potentially a new treatment for up to half of people with recurrent miscarriage. We know that doxycycline is given to some women experiencing miscarriage in other countries, but there has never been a proper trial conducted. And instead of just having your blood tested to look for causes of miscarriage, as is current practice, you will have the lining of the womb tested too so that we can identify those who will benefit from this treatment.

“Our aim is to try to improve the womb before you get pregnant. Most miscarriages occur within the first trimester (12 weeks) of pregnancy and our aim is to see a reduction in these early miscarriages.”

Researchers suspect that endometritis may be caused by an imbalance of the bacteria (microbiome) that live in the reproductive tract (the vagina, cervix, womb, fallopian tubes and ovaries). A healthy endometrium is important for the embryo to be able to attach to the womb and it is thought that endometritis disrupts this process, and can lead to a miscarriage. Treating endometritis with antibiotics may reduce endometritis by reducing disruptive bacteria and allowing the healthy bacteria to grow.

The trial will also use a complex adaptive design originally developed for cancer trials at the University of Warwick. During the trial, information will be analysed at regular intervals to see if the trial can be stopped early if results are greater than expected. In addition, the results will be presented as the probability that the treatment works and in which patients it works, rather than a simple yes or no answer. The process will be detailed in a talk for the British Science Festival by Professor Quenby and Dr Deepak Parashar from Warwick Medical School entitled ‘The maths of personalised medicine’ at 3pm on 12 September.

Professor Quenby added: “The special trial design means that we can answer a series of questions rather than just one as in a traditional trial. We will investigate what degree of inflammation is needed to cause miscarriage, how does inflammation cause miscarriage, does doxycycline reduce inflammation, does doxycycline alter the microbiome, does doxycycline reduce miscarriage, does doxycycline increase the number and time taken to achieve a live birth.”


Notes to editors:

More information on the CERM trial:


The study was funded by an MRC and NIHR partnership created to support the evaluation of interventions with potential to make a step-change in the promotion of health, treatment of disease and improvement of rehabilitation or long-term care.

1. The National Institute for Health Research (NIHR) is the nation's largest funder of health and care research. The NIHR:

· Funds, supports and delivers high quality research that benefits the NHS, public health and social care

· Engages and involves patients, carers and the public in order to improve the reach, quality and impact of research

· Attracts, trains and supports the best researchers to tackle the complex health and care challenges of the future

· Invests in world-class infrastructure and a skilled delivery workforce to translate discoveries into improved treatments and services

· Partners with other public funders, charities and industry to maximise the value of research to patients and the economy

The NIHR was established in 2006 to improve the health and wealth of the nation through research, and is funded by the Department of Health and Social Care. In addition to its national role, the NIHR commissions applied health research to benefit the poorest people in low- and middle-income countries, using Official Development Assistance funding.

2. The Medical Research Council is at the forefront of scientific discovery to improve human health. Founded in 1913 to tackle tuberculosis, the MRC now invests taxpayers’ money in some of the best medical research in the world across every area of health. Thirty-three MRC-funded researchers have won Nobel prizes in a wide range of disciplines, and MRC scientists have been behind such diverse discoveries as vitamins, the structure of DNA and the link between smoking and cancer, as well as achievements such as pioneering the use of randomised controlled trials, the invention of MRI scanning, and the development of a group of antibodies used in the making of some of the most successful drugs ever developed. Today, MRC-funded scientists tackle some of the greatest health problems facing humanity in the 21st century, from the rising tide of chronic diseases associated with ageing to the threats posed by rapidly mutating micro-organisms. The Medical Research Council is part of UK Research and Innovation.

This work uses data provided by patients and collected by the NHS as part of their care and support and would not have been possible without access to this data. The NIHR recognises and values the role of patient data, securely accessed and stored, both in underpinning and leading to improvements in research and care.

12 September 2019

For interviews or a copy of the paper contact:

Peter Thorley
Media Relations Manager (Warwick Medical School and Department of Physics)


Tel: +44 (0)24 761 50868

Mob: +44 (0) 7824 540863

If you would like to participate in the CERM trial, please get your GP to refer you, via the NHS choose and book system, to Professor Siobhan Quenby at the recurrent miscarriage clinic at:

University Hospitals Coventry and Warwickshire

Clifford Bridge Road