Imperial News

Researchers track mums-to-be in search for pre-eclampsia risk factors

by Franca Davenport

A unique new study will chart pregnancy from conception to birth, with the aim of identifying risk factors for pre-eclampsia.

Pre-eclampsia occurs in about five per cent of women and can be life-threatening for mother and baby. Severe pre-eclampsia contributes to about 15.9 per cent of maternal deaths in the UK and about 1,000 babies die each year because of the condition, mostly because of complications of early delivery.

Pre-eclampsia can affect healthy women who may initially have no apparent symptoms, which means they are often not recognised by health services until later in pregnancy. The cause of pre-eclampsia is still unclear. It has been linked to problems with the placenta but also the health of the mother’s heart and blood vessels (the cardiovascular system). Using state-of-the-art monitoring and scanning equipment, the CONCEIVE project will be the first to collect comprehensive cardiovascular data in a large number of women at a high level of detail from before the time of conception right through to birth. The researchers from Imperial College London will collect and analyse a large range of measurements to provide a comprehensive picture of early pregnancy.  

The project will be based at Queen Charlotte’s & Chelsea Hospital in west London with collaborators from the University of Cambridge. It is funded by the National Institute for Health Research (NIHR) Imperial Biomedical Research Centre (BRC) and Imperial College Healthcare Charity.

Dr Lin Foo, Clinical Research Fellow at the Department of Surgery and Cancer at Imperial College London, who will be running CONCEIVE, said: “This is a unique project. It is a fantastic opportunity for women to have their pregnancy and cardiovascular status documented closely as part of the study, and the data collected will be invaluable in helping our understanding of certain mechanisms associated with pre-eclampsia. By charting pregnancy from the very start and in such detail, we hope to identify factors that may be associated with the development of this disorder.”

Sarsha McEntee (42) from Ealing developed pre-eclampsia while pregnant with her second daughter, Nancy, who had to be delivered pre-term at 26 weeks on 14 February 2014. There had been no major problems with the birth of her first daughter, Isabella (21 months), and Sarsha had been healthy in the first half of her pregnancy with Nancy. The 20-week scan had shown no problems. At her 25-week midwife’s appointment, they had detected some protein in her urine but there were no concerns about Sarsha’s blood pressure at that point.

“It wasn’t until the next week that I began to feel unwell,” explained Sarsha. “It’s very difficult to explain it but I just felt odd and tired and, because I was pregnant and looking after a toddler, I didn’t think it was unusual. However the feeling got worse quite suddenly and, because of the protein in my urine, I decided to go to Ealing Hospital. In the maternity triage they found my blood pressure had rocketed to 220/140 and it was clear there was a problem.”

Once she was sufficiently stabilised, Sarsha was transferred to Queen Charlotte’s & Chelsea Hospital where Nancy was delivered at 26 weeks on Valentine’s Day. Due to internal bleeding from complications associated with pre-eclampsia, Sarsha was in a high dependency unit for seven days while Nancy was in hospital for over three months. “It was a really difficult time for all of us but they were simply amazing at Queen Charlotte’s. Words can’t describe what they did and now Nancy is a healthy, happy baby. It’s very difficult to say what pre-eclampsia feels like and I think that ‘being unable to describe it’ may ironically be an indication. A project like CONCEIVE could be incredibly valuable in helping to identify early risk factors for pre-eclampsia and improving awareness around the condition. Not only for mums-to-be but also for partners and family, who may notice the more subtle changes.”

The CONCEIVE project will aim to recruit 600 women who are planning to start a family and follow them over 12 months. The women will have an initial assessment, which will include various cardiovascular tests, such as detailed assessments of blood pressure, and cardiac output - the amount of blood pumped by the heart per minute. These tests are all safe and non-invasive, and will provide a much more comprehensive picture of cardiovascular health and information on any changes that occur during pregnancy.

Participants will also be provided with a fertility monitor to chart their fertility-associated hormone levels, and tests for pregnancy. This will provide valuable data on early pregnancy, including the date of ovulation and implantation of the fertilised egg to the wall of the womb. 

If participants become pregnant, in addition to standard scans at 12 and 20 weeks, which will be carried out as normal in their own hospitals, they will have a series of four scans at six, 10, 24 and 34 weeks gestation. At these times the mothers will also have cardiovascular measures taken as well as blood and urine tests.

Mr Christoph Lees, Reader at Imperial College London and the Head of Fetal Medicine at Imperial College Healthcare NHS Trust, who is the principal investigator of the project, said: “Because most women who get pre-eclampsia are in their first pregnancy and they are traditionally considered to be ‘low risk’, we currently have no idea which ones will develop pre-eclampsia. If we can identify them early on, then we could increase surveillance and ensure they get appropriate medical care at the appropriate time.”

Dr Foo added: “This is the first step in the journey. We are interested in investigating the possibility that women’s cardiovascular changes early in pregnancy may put them at risk of developing pre-eclampsia. There is already some suggestion that they are at risk of cardiovascular problems such as heart disease and stroke, and that pregnancy could be a barometer for these diseases in later life.”

The project is not a fertility study and will primarily look at the relationship between cardiovascular measures and the risk of developing poor pregnancy outcomes. However, the detail and amount of data could make it possible for researchers to analyse factors that influence successful conception in future research.

The CONCEIVE project is a collaboration between Imperial College London, the University of Cambridge and Imperial College Healthcare NHS Trust. Imperial researchers will collaborate with Professor Ian Wilkinson and Dr Carmel McEniery from the University of Cambridge, who are recognised international experts in cardiovascular function.

Participants in the study do not have to choose to give birth at Queen Charlotte’s & Chelsea Hospital.

For more information about the project and to register interest in participating, please email conceive@imperial.nhs.uk or telephone 07714051359.