sFlt-1 and PlGF are used to determine the ratio of sFlt-1/PLGF. The sFlt-1/PlGF ratio is a biomarker of placental insufficiency, and has proven clinical benefit as a rule-out test for pre-eclampsia. Similarly, an elevated ratio is associated with placental insufficiency and may contribute towards a diagnosis of pre-eclampsia in patients with supporting clinical and/or biochemical features of the condition.
Used as a pre-eclampsia marker for women >20 weeks gestation with:
• Suspected pre-eclampsia
• Isolated or worsening hypertension
• Isolated or worsening proteinuria
• Isolated fetal growth restriction
Turnaround time: 3hours routinely Mon-Fri between 9am-3pm. For urgent requests between 3pm-5pm, please phone the laboratory on x80885 otherwise testing will take place on the next weekday. This test is not available out-of-hours.
Performed by Endocrinology laboratory
Ambient (8 - 24 degrees Celsius)
If analysis is to take place within 48hrs of collection, storage and transport at 2-8°C is acceptable. Serum should be frozen if there is likely to be a delay of >48hrs between collection and analysis.
The sFlt-1/PlGF ratio is interpreted according to gestational age, as per the table below:
|≤38||>20+0||sFlt-1/PlGF ratio is in the normal range. The probability of developing pre-eclampsia in the next seven days is low.|
|38-84||20+0 to 33+6||Consistent with placental dysfunction, and a higher risk of adverse pregnancy outcome.|
|38-109||34+0 to 36+6|
|≥85||20+0 to 33+6||Consistent with severe placental dysfunction. In cases of suspected pre-eclampsia, this result is considered confirmatory.|
|≥110||34+0 to 36+6|
Results >38 will be flagged as abnormal
See above table for more information on interpretation.
Hughes, R et al; The predictive value of the sFlt-1/PlGF ratio in suspected pre-eclampsia in a New Zealand population: A prospective cohort study. Aust NZ J Obstet Gynaecol 2022: 1-8
Roche Electrochemiluminescence immunoassay
$300 (Exclusive of GST)
Please fully complete the dedicated sFlt-1/PlGF ratio request form.
Testing will not take place unless a gestational age is provided. This test is not valid for pregnancies less than 20 weeks’ gestation.
This test is for request by obstetric specialist only.
"*" indicates required fields