NHS to offer mums-to-be new blood test for pre-eclampsia

02/04/2019

Pregnant women in England will soon have access to a simple blood test which will screen them for the potentially life-threatening condition pre-eclampsia.

Currently women who show symptoms of pre-eclampsia undergo a number of tests, including hospital admission, so clinicians can try to determine whether they are at risk of developing severe pre-eclampsia. For those who have moderate to severe pre-eclampsia, clinicians may also choose to deliver their baby preterm to reduce the risk of the mother developing life-threatening complications. As well as increased hospital interventions creating stress for pregnant women as they wait for results, premature delivery can also affect a baby’s quality of life.   

Tommy’s PARROT trial found that the new PlGF (placental growth factor) blood test, speeds up diagnosis, and is particularly effective at determining which women are most at risk of developing the severest form of pre-eclampsia.

This means their condition can be better-managed and life-threatening complications to the mother and baby can be avoided. 

Furthermore, using PLGF alongside regular blood pressure and urine checks cut the average time to diagnosis from four days to around two.

More than 1,000 women at 11 UK maternity units took part in the trials during their second and third trimesters.

Tommy's Chief Executive, Jane Brewin said:

'Tommy’s is delighted that NHS England is making a new accurate test for pre-eclampsia widely available. This simple blood test will quickly identify the women at greatest risk of developing severe pre-eclampsia so they can be closely monitored and treated during their pregnancy. For other women with raised blood pressure this ‘rule out’ test will give women peace of mind and enable doctors to treat their condition more appropriately.'  

She went on to note:

'Ultimately this will ensure women receive the treatment and care they need, improving women’s maternity experience and their babies’ health.' 

Pre-eclampsia affects tens of thousands of pregnancies each year, but can be managed if spotted early. Those at higher risk should be very closely monitored and may have to have their baby delivered early if the condition becomes too severe despite treatment.

The NHS announced they will make the test, which costs £70 to £80, more widely available across the country in light of the new results. PiGF testing will soon be more widely available as evidence suggests it speeds up diagnosis which could save lives. 

Lead researcher Prof Lucy Chappell, from King's College London, said:

'This really is going to make a difference to women. The challenge for doctors is spotting which pregnancies are high risk and need closer monitoring. PLGF helps us reach that diagnosis earlier.'

The PARROT trial 

The PARROT trial examined the levels of a protein made by the placenta called placenta growth factor (PlGF), which can be detected by a simple blood test.

Previous studies have shown that women with very low levels of PlGF are more likely to develop severe pre-eclampsia, or have a stillborn baby.

Women with normal PlGF levels are at low risk, and can return to normal antenatal care. This means that care is focused on the women that really need it, while those that don’t avoid long stays in hospital. 

Professor Tony Young, from NHS England, said:

'The NHS, with partners in government, will be making this test more widely available across the NHS as part of our plans to ensure as many patients as possible can benefit from world-class health innovations.'

While the test has been available for three years, only three NHS England hospitals have used it routinely. The NHS in Wales, Scotland and Northern Ireland could choose to offer the test too.

What is pre-eclampsia

Pre-eclampsia is a condition that only occurs in pregnancy - typically after 20 weeks - and affects 2-8 in 100 women. It is diagnosed through a combination of hypertension (raised blood pressure) and proteinuria in pregnancy (the presence of protein in your urine).

Up to 6% of UK pregnancies will be affected by pre-eclampsia.

What are the risks of pre-eclampsia?

Most cases of pre-eclampsia are mild and may have no effect on the pregnancy.

However, if left untreated, pre-eclampsia can be dangerous for both the mother and baby.

Sometimes other organs, such as the liver, can become affected, and there can be problems with blood clotting.

Pre-eclampsia can potentially progress to a more dangerous condition known as eclampsia, which occurs in 1-2% of pregnancies.

Eclampsia can cause fits or convulsions. In severe cases, eclampsia can sometimes cause the death of the mother or the baby. Therefore, it is important to manage the condition safely.

Recent research highlights

• The CRADLE project is developing an easy, cheap way to measure blood pressure, helping to detect pre-eclampsia anywhere in the world
• The PHOENIX trial is researching the best course of action when pre-eclampsia develops before the baby is due and aims to recruit 900 women by the end of July 2018
• UV light could be used to help lower blood pressure and prevent pre-eclampsia