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Oxford University Hospitals NHS Foundation Trust
Clinical Biochemistry

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Soluble FMS-like Tyrosine Kinase -1

Also known as: sFlt-1, sFlt, pre-eclampsia marker

Specimen requirements

Sample type: Serum

Collection requirements: No special requirements


Price on application

Turnaround time

Please see Turnaround times

Analytical method


Analysis undertaken at these site(s)

John Radcliffe Hospital

Reference intervals

sFlt and PlGF are analysed in the context of suspected pre-eclampsia in accordance with NICE guidance DG23.

Concentrations of both markers change throughout pregnancy, so interpretation is on the basis of the sFlt : PlGF ratio and local guidance is available on the hospital intranet [] under Maternity Guidelines.

A ratio <38 between 20 and 34+6 weeks' gestation with a singleton pregnancy is associated with low risk (0.4 percent within seven days).