PARROT-2: Can repeated placental growth factor testing improve outcomes for women with symptoms of pre-eclampsia?

Tommy’s researchers have already found that a simple blood test can help to identify women at risk of severe complications from pre-eclampsia. Now they want to find out if there are benefits to repeating the blood test throughout pregnancy.

  • Authors list

    Professor Lucy Chappell, Dr Louise Webster, Professor Andrew Shennan, Dr Kate Duhig

    Start date: 2019
    End date: 2022

  • Research centre

  • Research status

    Completed projects

This project took place at our London centre which operated between 1995 and 2021.

Why do we need this research?

Pre-eclampsia is a common and potentially serious complication of pregnancy, which in rare cases can cause the death of the mother or the stillbirth of her baby. However, most cases of pre-eclampsia are mild and have no effect on the pregnancy. 

Women with symptoms of pre-eclampsia may need to be admitted to hospital for treatment and monitoring. Some women become unwell very quickly and need to have their baby delivered straight away. Others will need long stays in hospital so that they can be observed. 

In the PARROT study, researchers funded by Tommy’s showed that a simple blood test can be used to work out which women with symptoms of pre-eclampsia are most at risk of developing severe complications. The test measures the amount of a substance called placental growth factor (PlGF) in the blood. PlGF testing also helped to reduce the time it took to diagnose pre-eclampsia.

We now want to find out how often this test should be repeated during pregnancy.

What’s happening in this project?

Our researchers are carrying out a randomised controlled trial called PARROT-2, which will include over 1,200 women with symptoms of pre-eclampsia from more than 15 hospitals in the UK. The women will have blood tests throughout their pregnancies (from 22+0 to 35+6 weeks) to monitor their levels of PlGF. The researchers want to find out whether repeated testing reduces the chances of a baby dying or having to be admitted to a​​​​​​​ neonatal intensive care unit, and whether it also prevents further health complications for the mother.

What difference will this project make?

The results from the PARROT study led to NHS England making the PlGF blood test more widely available. In PARROT-2, we will find out if the blood test can be used even more effectively to identify the women at greatest risk of developing severe pre-eclampsia. We hope that this will enable even more mothers to get the care they need, increasing their chances of having a healthy baby.

  • We are very grateful to The Jon Moulton Charity Trust for funding this project.