Maternal blood biomarkers may help predict pregnancy-induced hypertension

Nov 18 2009

A new study that examines the value of maternal blood biomarkers will help identify and monitor patients at risk of developing preeclampsia and is set to change the way expectant mothers are cared for in prenatal clinics around the world.

The study, conducted by scientists at the highly-respected National Institute of Child and Human Development of the National Institute of Health (NICHD/NIH), set out to determine the diagnostic indices and predictive values of biomarkers measured in maternal blood in the first and second trimester of pregnancy. The goal of the study was to determine if the biomarkers could predict the subsequent development of preeclampsia.

"This study represents a very important step forward; for the first time ever, we are presented with the possibility, for clinical use, of a combination of factors to predict early onset preeclampsia with a reasonable degree of accuracy," says Professor Marshall Lindheimer, Professor Emeritus of Medicine and Obstetrics & Gynaecology at the University of Chicago.

Preeclampsia is the leading cause of infant death and the second leading cause of maternal death Around the world. Conservative estimates indicate that preeclampsia is responsible for some 76,000 maternal deaths and more than 500,000 infant deaths every year, according to the Preeclampsia Foundation. Early onset preeclampsia is the most dangerous form of this disease.

Known worldwide as 'the silent killer', preeclampsia is a disorder that occurs during pregnancy and after delivery. It is characterized by high blood pressure and the presence of protein in maternal urine. However, preeclampsia can affect other organs such as the liver, the kidney, the brain. Sometimes mothers develop seizures (eclampsia) and have intracranial haemorrhage which is the main cause of death. In some instances, women develop blindness when preeclampsia is severe. They may also suffer catastrophic complications such as liver rupture.

The findings of this new study are published in the November issue of the Journal of Maternal-Fetal & Neonatal Medicine.

"Left untreated, preeclampsia leads to serious - or fatal - complications for both the mother and baby," says Dr Kusanovic of the Perinatology Research Branch of the NIH and Wayne State University/Hutzel Women's Hospital in Detroit, Michigan and lead author of the study.

"Our study found that maternal plasma concentrations (of angiogenic and antiangiogenic factors) together with a combination of other demographic, biochemical and biophysical factors are useful in assigning risk for the subsequent development of early-onset preeclampsia," explains Dr Roberto Romero, Chief of the Perinatology Research Branch of the NIH, who is one of the world's leading experts on this condition and in the study of complications of pregnancy.

"The establishment of an accurate means to assess the risk for preeclampsia will enable health care practitioners to identify women who require more intensive monitoring to safeguard both mother and baby from this devastating condition," says Dr Romero.

Dr Mario Merialdi, Coordinator for Improving Maternal and Perinatal Health at the World Health Organisation (WHO) said: "The results of the study conducted by the international team led by Dr Romero have important implications for clinical practice and public health policies. Hypertensive disorders of pregnancy are one of the major causes of maternal and fetal mortality worldwide."

"Reliable screening tests that could identify women at risk for developing preeclampsia are not yet available and the findings of Kusanovic et al. provide the scientific basis for the development of such tests," explained Dr Merialdi.

"The World Health Organization, in collaboration with the Perinatal Research Branch of the NICHD, is presently analyzing samples collected in more than 10,000 pregnancies in eight countries around the world to further validate the results obtained by Dr Romero's scientific team."