11 babies are stillborn in the UK every day and recent research funded by Sands, the stillbirth and neonatal death charity, and managed by Wellbeing of Women, shows that ICP (intrahepatic cholestasis of pregnancy) may be one of the causes. There has been debate about whether there is a risk of stillbirth with ICP but this study, the largest of its kind so far, has shown a three-fold increase in the risk of stillbirth for women with severe ICP (from 0.5 to 1.5%).
The study, recently published in Hepatology online, was undertaken by Professor Catherine Williamson and Doctor Victoria Geenes, at the Institute of Reproductive and Developmental Biology, Imperial College London and Women’s Health Academic Centre, King’s College London. It is the largest study to date of the effect of severe cholestasis on perinatal outcome, and the first to show a significantly increased association with stillbirth. This risk rises as the mother’s bile acids become higher. The study may have implications for current management guidelines of pregnancies with severe ICP.
ICP (also known as obstetric cholestasis) is a pregnancy-specific liver disease that occurs in 1 in 200 pregnancies and affects around 5,000 women each year in the UK. It typically develops in the third trimester of pregnancy (but can be earlier) and its main symptom is itching. This itching can be mild or so severe that women scratch themselves until their skin bleeds, is often on the hands and feet but can be generalised, and tends to be more noticeable at night. It is diagnosed by excluding other causes of itch and by measuring the amount of bile acids in the mother’s blood. Severe ICP (bile acids over 40 mmol/L ) occurs in around 1 in 1,000 pregnancies. Professor Williamson studied the data on 713 women with severe ICP (collected by the UK Obstetric Surveillance System, UKOSS, a register for rare disorders of pregnancy) and compared them to a control group of low-risk women.
Previous smaller case series have suggested that severe cholestasis is associated with adverse outcomes for the baby including preterm labour, fetal distress (indicated by meconium staining of the amniotic fluid), low Apgar scores on delivery and stillbirth. This study confirms these risks and further, that they grow with increased measures of bile acids in the mother’s blood. Peak bile acid levels were also significantly higher in the stillbirth cases. This suggests that bile acids should be routinely used to monitor ICP as this may give an indication of the baby’s wellbeing.
Janet Scott, Head of Research and Prevention at Sands, said: “Over 4,000 babies are stillborn every year in the UK, devastating the lives of thousands of families. Clearly some of these deaths are avoidable with improvements to care in high-risk pregnancies. This important piece of research into the impact of ICP may help save precious lives.”
Professor Williamson, who is now based at King’s College London but retains close links with Imperial College London, said: “We are very grateful to Sands and Wellbeing of Women for their support of this study. We hope this work will assist obstetricians and midwives in deciding which women are at risk of these complications and that bile acid measurement will become an accepted part of obstetric management of cholestasis of pregnancy.”
Jenny Chambers, Founder of ICP Support says; "As a mother who has suffered two stillbirths I am only too aware of the need for clinicians to remain vigilant to the risks associated with ICP but to do this they need a clear guideline to follow. We hope that this very important study will enable the refinement of the current RCOG guideline which may help to protect future unborn ICP babies. We are indebted to Sands for supporting something that could save babies’ lives."