Miscarriage breakthrough: how groundbreaking Warwick research has shed light on the mystery of repeated pregnancy loss

For decades, the countless families affected by the misery of miscarriage have been left without answers, pregnancy loss after pregnancy loss.

Now, researchers at the University of Warwick have uncovered a hidden biological mechanism within the womb that could explain why some pregnancies fail - even when the embryo is healthy.

Miscarriage affects around one in six pregnancies, most occurring before 12 weeks. While chromosomal abnormalities in embryos have long been recognized as a major cause, the role of the womb lining - the endometrium - has remained largely unexplored. This major new study changes that.

Revealing the Missing Piece

The study analyzed over 1,500 biopsies from more than 1,300 women, revealing that a critical process known as the decidual reaction - where the womb lining transforms to support embryo implantation - often malfunctions in women with a history of miscarriage. This dysfunction creates an unstable environment that can allow implantation but increases the risk of bleeding and early pregnancy loss.

What’s striking is that this abnormal response isn’t random: it recurs across menstrual cycles, suggesting a consistent and measurable biological pattern. Some women may therefore be experiencing a womb ‘primed’ for failure, explaining why miscarriage often recurs in the same women - even with healthy embryos.

Dr Joanne Muter, first author and researcher at Warwick Medical School, explains: “Many women are told they’ve just had ‘bad luck’, but our findings show that the womb itself may be setting the stage for pregnancy loss, even before conception takes place.”

“ Many women are told they’ve just had ‘bad luck’.”

From Study to Screening

The study, which was led by the University of Warwick and University Hospitals Coventry and Warwickshire (UHCW) NHS Trust, with support from pregnancy charity Tommy’s and the Wellcome Trust, also found that experiencing one miscarriage increases the likelihood of future abnormal womb responses. This insight further explains why pregnancy loss often recurs in some women, reframing miscarriage not as a series of isolated events, but as a compounding biological vulnerability.

The lead author of the study, Jan Brosens, Professor of Obstetrics & Gynaecology at Warwick and UHCW NHS Trust, notes: “Each miscarriage increases the risk of an embryo implanting in an abnormal womb lining, regardless of age. We now have the tools to screen for preventable miscarriage risk and evaluate treatments that improve the womb lining before pregnancy.”

On the back of this discovery, the team developed a diagnostic test to measure the molecular signals of a healthy or dysfunctional decidual reaction. The test has already helped over 1,400 patients understand their womb readiness, and identify modifiable factors before pregnancy begins. The University of Warwick is launching a spin-out company, Xambika Biotechnology Ltd, with the aim to make the test available across the United Kingdom and Europe next year.

From Study to Screening

The study, which was led by the University of Warwick and University Hospitals Coventry and Warwickshire (UHCW) NHS Trust, with support from pregnancy charity Tommy’s and the Wellcome Trust, also found that experiencing one miscarriage increases the likelihood of future abnormal womb responses. This insight further explains why pregnancy loss often recurs in some women, reframing miscarriage not as a series of isolated events, but as a compounding biological vulnerability.

The lead author of the study, Professor Jan Brosens, Professor of Obstetrics & Gynaecology at Warwick and UHCW NHS Trust, notes: “Each miscarriage increases the risk of an embryo implanting in an abnormal womb lining, regardless of age. We now have the tools to screen for preventable miscarriage risk and evaluate treatments that improve the womb lining before pregnancy.”

On the back of this discovery, the team developed a diagnostic test to measure the molecular signals of a healthy or dysfunctional decidual reaction. The test has already helped over 1,400 patients understand their womb readiness, and identify modifiable factors before pregnancy begins. The University of Warwick is launching a spin-out company, Xambika Biotechnology Ltd, with the aim to make the test available across the United Kingdom and Europe next year.

From Research to Real-World Impact

For video games producer Charlotte ‘Charlie’ Beattie, the test marked a turning point.

Charlie had initially suffered an ectopic pregnancy - a non-viable pregnancy where a fertilized egg implants itself outside of the womb - while she and husband Sam were on their honeymoon in Mauritius. She then had seven or eight further early pregnancy losses.

“I was very sad,” said Charlie. “I felt it was never going to happen for us.” Charlie and Sam had reached a stage where “a positive pregnancy test wasn't exciting anymore.”

“A positive pregnancy test wasn't exciting anymore.”

Charlie was told about the work of Professor Brosens, and a subsequent biopsy showed that her womb was not doing what it was meant to do. After treatment for three months to improve her womb lining, Charlie became pregnant again.

“That is the pregnancy that stuck,” added Charlie, who gave birth to baby June in April 2025. “I’m absolutely ecstatic. We’d started talking about adoption or just being an uncle and auntie, so we are absolutely thrilled. She is a little miracle, and we are very grateful.”

Turning Chance into Choice

Charlie’s story joins others whose lives were transformed by this research. One of the patients offered the new test, Holly Milikouris, a civil servant from Cheshire, had suffered five consecutive miscarriages before enrolling in the trial.

Holly’s diagnostic test revealed that her womb lining prepared poorly for pregnancy which had affected the development of her embryos. After undergoing treatment by Professor Brosens, she and her husband Chris went on to have two healthy children, three-year-old George and one-year-old Heidi.

Holly’s story underscores the heavy emotional toll of miscarriage, and the transformative power of personalized care.

“We felt lost and were beginning to accept that I might never successfully carry a pregnancy,” Holly recalls. “The treatments that typically can help women who have experienced miscarriages hadn’t worked for us and each time we tried again we felt like we were rolling a dice with the baby’s life.

“Being given the opportunity to take part in this trial was life changing. For the first time the results of my biopsy were normal, and we went on to have not one, but two successful pregnancies.

“We will never be able to thank Professor Brosens enough and are hopeful that the results of this groundbreaking study will help many other families.”

“Being given the opportunity to take part in this trial was life changing.”

Rethinking Reproductive Medicine

As reproductive medicine evolves, this study marks a milestone. It invites clinicians, researchers, and policymakers to rethink how we approach miscarriage - not as an inevitability, but as a preventable condition rooted in biology we’re only now beginning to understand. Current fertility diagnostics focus heavily on embryos, hormone levels, and genetics. This breakthrough research shifts the spotlight to the womb itself, positioning the endometrium as a key player in early pregnancy health.

As this diagnostic approach now expands beyond the pilot project, it holds promise, not only for individual families searching for answers, but also for reshaping the trajectory of miscarriage care across the UK and beyond.

It opens new avenues for pre-conception care, personalized treatment, and - perhaps most importantly - hope, for women who have gone too long without answers.

This content was paid for and created by the University of Warwick. The editorial staff of The Chronicle had no role in its preparation. Find out more about paid content.