sFlt‑1/PlGF ratio
Chemical Pathology
Notes
Pre-eclampsia is a serious complication of pregnancy characterized by hypertension and proteinuria after 20 weeks of gestation. In patients with signs and symptoms of pre-eclampsia, the measurement of soluble fms‑like tyrosine kinase‑1 (sFlt-1) and placental growth factor (PIGF), and subsequent calculation of sFlt‑1/PlGF ratio, has been proven to be helpful in the short-term prediction of the disease.
sFlt-1/PlGF ratio can also improve the prediction of early-onset pre-eclampsia for women with risk factors including intrauterine growth restriction (IUGR); pre-eclampsia; eclampsia; haemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome; pre-gestational diabetes; abnormal uterine artery Doppler ultrasound.
- Only available to midwifery and obstetrics
- Testing recommended in pregnancy 20 weeks to 34+6 weeks, with suspected pre-eclampsia.
Sample Requirements
Blood taken into a 5mL rust/gold top gel tube
Storage
Do not store but send at ambient temperature to the laboratory.
Required information
Please give gestational age on all requests.
Turnaround times
The assays are run throughout the day and night. Results are normally available within 4 hours. The test can also be ordered as an urgent request.
Reference ranges
A ratio of:
- ≤38: 0.4% risk of PET in the next 7 days, <3% risk in 28 days
- >38 to ≤85: 20% risk PET in the next 7 days
- >85: very high risk (56%) of pre-eclampsia in the next 7 days
For full pathway and interpretation please see local maternity guidelines: M1049 AC13
Further information
To learn more about pre-eclampsia visit Royal College of Obstetricians and Gynaecologists
Page updated: 17/05/2023