New research shows certain treatment can reduce risk of preterm birth

Scientists at our London Research Centre recently published a study that shows a treatment called ursodeoxycholic acid (UDCA) can reduce the risk of premature birth in mothers with a liver condition known as intrahepatic cholestasis of pregnancy (ICP) by more than 40%.

What is ICP?

ICP is a potentially serious liver disorder which can develop during pregnancy. It happens when the acids in a woman’s bile do not flow properly from the liver to the gut; instead of helping digest food, as they should do, the acids build up in the body instead.

The main symptom of ICP is itching, normally without a rash, but other signs might be dark urine or pale poo. Symptoms will generally start towards the end of pregnancy, but it’s possible to develop the condition as early on as 8 weeks. It affects around 5,500 women in the UK each year, and is most common among South Asian and Latin American women.

ICP can be a problem because it’s known to increase the chances of some serious pregnancy complications. More than 1 in 10 women with ICP give birth prematurely, leaving their babies more likely to be admitted to a neonatal care unit and vulnerable to lifelong health problems, and mothers with severe disease face higher risk of stillbirth.

Latest Tommy’s research

The most common treatment for ICP is ursodeoxycholic acid (UDCA) but research so far hasn’t found clear evidence of how well it works. Tommy’s researcher Prof Catherine Williamson led her team at King’s College London and Guy’s & St Thomas’ NHS Trust in investigating whether UDCA is the best way of treating the condition.

Our pregnancy experts analysed data for over 7,000 women from across the world to explore the benefits of UDCA on ICP in preventing premature and stillbirths. Their findings in world-renowned medical journal the Lancet are that UDCA significantly reduced the risk of premature birth in mothers with ICP - particularly when they were pregnant with a single baby.

We also learned from this research that UDCA treatment has the most benefit for mothers with more severe ICP, who face the highest risk of premature birth. Putting this new knowledge into practice will help the most vulnerable families to get the care they need.

As well as premature birth, the study measured a combined pregnancy outcome with stillbirth, because these losses are so rare that numbers would otherwise be too small for us to see clear results. The team noticed a reduced risk of stillbirth in randomised controlled trials, but didn’t see a significant effect in other types of research, so more detailed investigation is needed.

Why this matters

Knowing that UDCA will give mothers who develop ICP have a better chance of carrying their baby to term is a crucial finding. Premature birth is the leading cause of neonatal death in the UK, so we need to prevent it wherever possible, and helping mothers with ICP to continue their pregnancy for as long as possible is a huge benefit of UDCA.

When Lizzie showed symptoms of ICP, she was prescribed UDCA by her GP and saw an instant improvement once she started taking the treatment. She said: “UDCA enabled me to enjoy my pregnancy again. I took the treatment from the end of December through to the end of my pregnancy in March; Alexander arrived only 10 days early.”

Knowing that UDCA reduces the chance of a spontaneous premature birth, it would definitely be something I would choose to take again.

Our CEO Jane Brewin explained: “Professor Williamson’s team put this cutting-edge research into practice at Tommy’s specialist pregnancy clinics, but everyone should be entitled to the best possible care for themselves and their babies, so we hope this drug can become widely available to improve support for all those on difficult pregnancy journeys.”

With 60,000 babies born prematurely in the UK each year, and mothers with ICP facing higher risks, this is an important step in making pregnancy safer for vulnerable families.

Research author Catherine Williamson, professor of women’s health at Kings College London and honorary consultant in obstetric medicine at Guy’s & St Thomas’ Hospital, added: “It’s excellent to discover that UDCA works best for women with more severe ICP, as these women are at greater risk of spontaneous preterm birth.”

We hope our research will inform clinical practice and guidelines, as we’ve found UDCA to be beneficial to women with ICP and their babies.