Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Preeclampsia is a serious complication of pregnancy characterized by hypertension and proteinuria after 20 weeks of gestation. It occurs in 35 % of pregnancies and is still one of the leading causes of foetal and maternal morbidity and mortality. Preeclampsia appears to be due to the release of angiogenic factors from the placenta, such as placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1). In women who develop preeclampsia, sFlt-1 levels have been found to be higher and PlGF levels have been found to be lower than in normal pregnancy.
NICE recommends to “offer placental growth factor (PlGF)-based testing to help rule out pre-eclampsia in women presenting with suspected pre-eclampsia (for example, with gestational hypertension) between 20 weeks and up to 35 weeks of pregnancy” (NG133).
Specimen container adult:
Serum (SST tube)
Minimum volume adult:
1 mL
Sample stability:
Unseparated sample: unknown
Separated sample: 2 days at 2° to 8°C, 6 months at -20°C
Interpretation:
Please refer to the Trust guidelines
Reference ranges :
At 36 gestational weeks, an sFlt-1/PlGF ratio ≤ 38 had a negative predictive value for severe preeclampsia of more than 99 % (Sovio et al, 2017).