A team of UK researchers has found that women who develop pre-eclampsia in pregnancy have lower than normal levels of a marker protein in their blood at the three-month stage and this could open the door to developing a simple blood test for this potentially life-threatening condition.

The research, which was funded by the British Heart Foundation (BHF), was led by Professor Dave Bates from the Department of Physiology and Pharmacology at the University of Bristol and is published in the journal Clinical Science.

Pre-eclampsia is a common pregnancy-related condition characterized by high blood pressure, protein in the urine, fluid retention, and dysfunction in the lining of blood vessels of the pregnant woman. Up to 1,000 babies and 10 women die every year in the UK as a result of the condition.

Bates and colleagues found that women in their 12th week of pregnancy who went on to develop pre-eclampsia had lower than expected levels of the protein VEGF165b compared to counterparts who did not develop the condition.

They suggested VEGF165b could be used as a biomarker to assess a woman’s risk of developing pre-eclampsia and a test based on it could be used to monitor and care for vulnerable pregnancies.

The researchers built on previous studies that suggested links between pre-eclampsia and the VEGF group of proteins. They decided to track the level of VEGF165b in particular.

For the study, Bates and colleagues measured levels of VEGF165b in non-pregnant women, women who did not develop pre-eclampsia and women who did. In the pregnant women they measured levels of VEGF165b at 12 weeks of gestation and intervals through the rest of the pregnancy.

The results showed there was a 10-fold increase in VEGF165b in normal pregnancies at 12 weeks compared to non-pregnancy, while women who went on to develop pre-eclampsia hardly showed any increase at week 12.

Yet at full term, there was no statistically significant difference in the levels of VEGF165b between the women with pre-eclampsia and the women with normal pregnancies. The researchers suggested that VEGF165b increase is delayed in women who go on to develop pre-eclampsia.

43-year-old Karen Partridge from Bristol had severe pre-eclampsia in her first two pregnancies. She said she had to spend 21 days in hospital in her first pregnancy and that it was “a scary time”.

She had the classic symptoms, she said:

“Protein in my urine, and high blood pressure and I swelled up like the Michelin man putting on four stone.”

Partridge said she had no choice but to have her first baby delivered as quickly as possible and this meant her daughter had a low birthweight of only 5lb 2 oz (2.3 kg) and had to be fed through a tube for her first 10 days of life.

Again, Partridge found herself with pre-eclampsia and very similar symptoms during her second pregnancy, and again it was a very anxious time for her and her family.

“Early detection would have prepared me for the symptoms of this condition and my pregnancy would have been more closely monitored,” she said in a statement from Bristol University.

Dr Victoria Bills, the obstetrician who conducted the study and who is also a Clinical Research Fellow at the University said:

“Although there is currently no medicine to cure pre-eclampsia, a VEGF test could guide the prescription of aspirin — which decreases the incidence of pre-eclampsia by 15 per cent — and identify women that should be particular mindful of the symptoms, and who should be monitored closely by their doctor and midwife with regular fetal growth scans and blood pressure measurement.”

“As this change occurs so early we still need to know whether the VEGF165b contributes to development of the condition, or is a consequence of early changes,” she added.

Professor Jeremy Pearson, Associate Medical Director at the BHF likened the medical research quest to develop a test to predict pre-eclampsia to a “holy grail”.

“These researchers have made a vital finding that, if confirmed by other studies, has the potential to translate into a simple test that could potentially save many lives,” said Pearson.

“Failure to upregulate VEGF165b in maternal plasma is a first trimester predictive marker for pre-eclampsia.”
Victoria L Bills, Julia Varet, Ann B Millar, Steven J Harper, Peter W Soothil and David Bates.
Clinical Science, Published as Immediate Publication 1 October 2008. doi:10.1042/CS20080270

Click here for Abstract.

Sources: Bristol University.

Written by: Catharine Paddock, PhD.