Pre-eclampsia is a pregnancy complication characterized by high blood pressure and possible organ damage and is the second leading cause of maternal mortality. Though symptoms generally manifest late in pregnancy, low-dose aspirin therapy at 12-28 weeks can reduce risk but is only recommended for those with risk factors. However, most patients who develop pre-eclampsia do not have risk factors or a family history of the complication.

Therefore, identifying patients without known risk factors who may develop pre-eclampsia is an important advance, both for preventative treatment and for potentially enrolling patients in clinical trials for pre-eclampsia.

A recent paper published in the journal Cell has done just this. The researchers used extracellular RNA, which are small RNAs that are loaded onto proteins or into small packets of information called vesicles and released into body fluids, to identify women with a risk of developing pre-eclampsia. 

Using a technique called small RNAseq, they sequenced RNA in the blood samples of 212 women, 73 of whom had developed pre-eclampsia and 139 controls. They looked for RNAs that were present only in women who developed pre-eclampsia, then checked if those RNAs were found in the control cohort. They identified several miRNAs (one of many small RNA types) which could separate women who went on to develop pre-eclampsia from those who did not.

Creating this simple blood test could affect the outcomes of all patients without known risk factors for pre-eclampsia. Normally, they would be unaware of their risks and would not take preventative measures. The researchers are hopeful that this will eventually make its way into the clinic, where it could save many women's lives.