In women with suspected preeclampsia presenting at <34 weeks, circulating sFlt1/PlGF ratio predicts adverse outcomes occurring within two weeks. The accuracy of this test is substantially better than current approaches and may be useful in risk stratification and management. Additional studies are warranted to validate these findings.
So for women tested before 34 weeks, measuring how much soluble FLT and how much placental growth factor were in the maternal bloodstream, and expressing them as a ratio had very statistically significant predictive value for stuff going explosively wrong. But of course, this needs to be confirmed by an independent research team or two (to rule out confirmation bias - finding what you want to find!) and developed into a commercial test if it's confirmed.