New research highlights a more accurate way to screen for pre-eclampsia in pregnant women than currently recommended methods. Published online in Ultrasound in Obstetrics & Gynecology, the study challenges the UK’s current guidelines on the management of hypertensive disorders during pregnancy.
Pre-eclampsia (PE) affects approximately 2% to 3% of pregnancies and can have serious health effects for both the mother and child. The condition is characterized by high blood pressure. Some affected women develop very severe disease associated with kidney, liver, bleeding and neurological problems. The fetus may experience impaired growth and possibly die. Risks are especially high when PE leads to preterm birth before 37 weeks’ gestation (preterm-PE), which itself is associated with long-term health issues for the children.
Recent evidence suggests that giving low-dose aspirin to women at high risk of the disorder can reduce the prevalence of the severest form of PE by more than 60%, but the treatment must be started before 16 weeks’ gestation. Therefore, early detection of the condition is important. In the UK, identification of high-risk women who could benefit from aspirin is based on a checklist of maternal characteristics and medical history as defined by the National Institute for Health and Care Excellence (NICE) guidelines. An alternative approach combines known risk factors with the results of various maternal biophysical and biochemical measurements performed at 11-13 weeks’ gestation (mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), and serum placental growth factor (PlGF)), known as the first-trimester combined test.
This latest Ultrasound in Obstetrics & Gynecology study—called the Screening ProgRamme for prE-Eclampsia (SPREE) study—was designed to compare the performance of first-trimester screening for PE by this alternative approach with that of the current NICE method. The study was conducted in seven National Health Service (NHS) maternity hospitals in England between April and December 2016. Singleton pregnancies at 11 to 13 weeks’ gestation had recordings of maternal characteristics and medical history, as well as measurements of MAP, UtA-PI and PlGF.
PE occurring at any point during pregnancy (all-PE) was found in 473 (2.8%) of the 16,747 pregnancies in the study, and preterm-PE was seen in 142 (0.8%). The detection rates of the NICE checklist for all-PE and preterm PE were 30.4% and 40.8%, respectively. Furthermore, compliance with the NICE recommendation that women at high risk for PE should be treated with aspirin from the first trimester was only 23%. If screening was carried out by the first-trimester combined test, the detection rates for all-PE and preterm PE were increased to 42.5% and 82.4%, respectively.
The findings indicate that the use of the simple algorithm based on maternal characteristics and easily measurable markers can identify approximately 80% of women who would go on to develop preterm-PE and would therefore benefit from taking prophylactic aspirin. The first-trimester combined test is freely available as a simple and user-friendly risk calculator via www.fetalmedicine.org and on the Fetal Medicine Foundation app.
“The SPREE study has provided definitive proof to support risk-based screening for preterm-PE using various biomarkers. It is now time to revise the professional guidelines and to move away from using a checklist-based method for screening.” said co-senior author Liona Poon, MD, of King’s College London, in London. Dr Poon is also a member of ISUOG's international faculty.
Basky Thilaganathan, MD, PhD, UOG journal’s Editor-in-Chief, noted that the findings have important clinical implications. “Poon and colleagues have demonstrated that effective early pregnancy screening for preeclampsia is possible in a routine NHS hospital setting. They make a compelling case for the routine implementation of this protocol to halve the cases of early-onset severe preeclampsia cases in the UK” he said.
Professor in Fetal Medicine at St George’s Hospital, University of London, Director of Fetal Medicine at St George’s Hospital, former Editor-in-Chief UOG 2011-2018
Prof. Basky Thilaganathan is a specialist in the medical and surgical management of highrisk pregnancies (materno-fetal medicine) with a focus on twin pregnancy, fetal growth, fetal abnormality and pre-eclampsia. Prof. Thilaganathan's research methods include uterine Doppler and trophoblast invasion, screening for pre-eclampsia, echocardiography-based studies of maternal cardiac adaptation to pregnancy, and clinical studies of twin pregnancies.
He has authored two undergraduate and five postgraduate textbooks in obstetrics and fetal medicine and is the lead trainer for the Maternal-Fetal medicine sub-speciality training programme at St George’s Hospital, London. Prof. Thilaganathan was Editor-in-Chief of ISUOG’s Ultrasound in Obstetrics and Gynecology for nearly 8 years, within that time raising the Journal’s impact factor to 5.654. Furthermore, he has authored over 200 peer-reviewed publications in indexed journals. He is a Council Member of the Royal College of Obstetricians and Gynaecologists (RCOG), member of the National screening Committee and also the Clinical Lead
for the first dedicated high-throughput NIPT lab in the UK NHS to undertake cfDNA aneuploidy screening in pregnancy.
Executive Committee, Finance & Risk Committee, Nominations Committee, China Task Force, UOG Editorial Board
Professor Liona Poon is an Academic Subspecialist in Maternal Fetal Medicine, devoted in improving maternal and fetal health. She has had a prolific research output throughout her clinical and research posts, including over 130 peer-reviewed publications in high impact international journals. In the last 10 years she has focused her research on establishing a programme for effective early prediction and prevention of preeclampsia, a major cause of maternal and perinatal morbidity and mortality. With her success in developing a first-trimester prediction model for preeclampsia using maternal risk factors, ultrasound, blood pressure and biochemical markers, and on Aspirin prophylaxis against preeclampsia, her goal in the next 10 years is to improve obstetric care worldwide, through clinical research and education.
Notable Publications:
Aspire trial: incidence of preterm preeclampsia in patients fulfulling ACOG and NICE criteria according to risk by the FMF algorithm. Poon LC, Rolnik DL, Tan MY, Delgado JL, Tsokaki T, Akolekar R, Singh M, Andrade W, Efeturk T, Jani JC, Plasencia W, Papaioannou G, Blazquez AR, Carbone IF, Wright D, Nikolaides KH.
Ultrasound Obstet Gynecol 2018 Jan 30. doi: 10.1002/uog.19019 [Epub ahead of print]
Aspirin versus Placebo in Pregnancies at High Risk of Preterm Preeclampsia. Rolnik DL, Wright D, Poon LC, O'Gorman N, Syngelaki A, de Paco Matallana C, Akolekar R, Cicero S, Janga D, Singh M, Molina FS, Persico N, Jani JC, Plasencia W, Papaioannou G, Tennebaum Gavish K, Meiri H, Gizurarson S, Maclagan K, Nicolaides K.H.
New England Journal Medicine 2017, 2017 Jun 28. doi: 10.1056/NEJMoa1704559. [Epub ahead of print]
Country: China, Hong Kong Special Administrative Region
Field: Obstetrics
Specialties: Fetal anomaly screening 1st trimester and 2nd trimester; fetal biometry and wellbeing; fetal anomalies screening; aneuploidy screening; fetal anomalies; fetal growth restriction; maternal and fetal Doppler; multiple pregnancy; preeclampsia; preterm delivery; fetal growth; detection of fetal and neonatal growth abnormalities; ultrasound on the labour ward
Languages: English; Chinese (Mandarin); Chinese (Cantonese)