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Placental growth factor-based testing to rule out pre-eclampsia


Quick, accurate blood tests which can help rule out pre-eclampsia are contributing to safer pregnancies and better outcomes for tens of thousands of pregnant women and their unborn babies every year. More accurate diagnosis reduces the need for admission and enables a clearer focus on women needing closer monitoring. The pandemic has underlined the importance of safe and effective care, and minimising unnecessary hospital admissions. Within four years of the first real world evaluation in the Oxford AHSN region there has been widespread adoption of placental growth factor (PlGF) testing into standard clinical practice due in large part to a rapid adoption project led by AHSNs. By April 2022, 86% of eligible maternity units in England had either adopted or were implementing the test. This is an example of AHSNs understanding the challenges to adopting new technology and helping the NHS and innovators work together to overcome them.


Pre-eclampsia (PE) is a multi-system hypertensive disorder – a serious disease that complicates around four per cent of all pregnancies – usually in the latter stages. It adversely affects thousands of women and their babies every year and can lead to small birth weight babies, organ damage and – in extreme cases – death. It is not unusual to induce the baby early, even with mild pre-eclampsia.

Correctly diagnosing PE is notoriously difficult. Clinical teams have a high degree of suspicion for PE and a low threshold to admit pregnant women with suspected PE. However, only a small proportion of these go on to develop it. This places significant economic and capacity burdens on maternity systems. It costs the NHS an estimated £9,000 per pregnancy to treat. There has previously been no definitive way to accurately diagnose who is not at risk of developing pre-eclampsia. Women are routinely admitted for an anxious few days of hospital tests ‘just in case’ – but most do not actually have the condition. Based on the NICE guidance DG23 Resource Impact Model hospital admissions related to pre-eclampsia could be reduced by more than one third.


In 2017, the Oxford AHSN initiated a project to increase uptake and adoption of placental growth factor-based (PlGF) testing which highlights women who are likely to develop pre-eclampsia within 7-14 days. The blood test can be taken as part of routine checks at between 20 weeks and 34 weeks plus 6 days of pregnancy in line with NICE guidance. The test supports clinical decision-making by providing an objective measurement to combine with other clinical symptoms, such as high blood pressure, blurred vision or high protein in urine.

Working with the Oxford Patient Safety Collaborative and clinical leads, laboratory heads, finance and management functions, the Oxford AHSN helped three of the first hospitals in England to adopt PlGF-based testing into standard clinical practice.

This successfully demonstrated that by offering tests to women suspected of having pre-eclampsia clinical teams were better able to identify women who did not have the disease and could safely be sent home, avoiding unnecessary hospital admissions for monitoring. It provided a platform for wider spread and adoption – both within and beyond the Oxford AHSN region. The Oxford AHSN developed an implementation pack to support this work. This supports a collaborative, multi-disciplinary approach including changes required to pathways and practices. For each maternity unit AHSNs are developing insight into their unique pathway and needs and providing project management and business support behind the adoption process.

The test was selected for the NHS England Accelerated Access Collaborative, Innovation Technology Payment and Rapid Uptake programmes which introduce an accelerated pathway to market for highly transformative innovations. From April 2019 providers of maternity services were able to adopt and implement either the Quidel Triage PlGF test or the Roche Elecsys sFlt-1:PlGF ratio test fully funded, as NHS England centrally reimbursed the suppliers directly.

All AHSNs, led by the Oxford AHSN, have been working together to ensure rapid and widespread adoption of the test into standard clinical practice in maternity units across the country.

By April 2022, 86% of eligible maternity units in England had either adopted or were implementing PlGF testing. In 2020/21 more than 40,000 women benefited from the test. Projected annual savings in England are estimated at £4m per year relating to reduced hospital bed occupancy.

In March 2021 the Oxford AHSN delivered a workshop on overcoming barriers to adopting placental growth factor testing as part of Bridging the Gap, an AHSN Network event offering insights and guidance to healthcare industry innovators. From April 2021 PlGF-based testing is one of four technologies included under the new NHS MedTech Funding Mandate.

The Oxford AHSN’s pre-eclampsia work secured two prizes in 2019: an HSJ Partnership Award and a Univants of Healthcare Excellence Award. It was also a finalist in the HSJ Awards.


“The Oxford AHSN supported us all the way” – Chris Hudson, Roche Diagnostics. Read more

Environmental impact

In July 2021 the Oxford AHSN and Sustainable Healthcare Coalition published a report highlighting how PlGF-based testing for pre-eclampsia has additional environmental benefits. In addition to the benefits of widespread PlGF testing outlined above, it concluded that the consequent cut in patient journeys and overnight hospital stays could potentially save 1,149 tonnes CO2e – equivalent to three million miles of car travel each year in England. Read more about the environmental benefits of testing to rule out pre-eclampsia in this case study.