Angiogenic profile in the Finnish Genetics of Pre-Eclampsia Consortium (FINNPEC) cohort

To study first and second/third trimester levels of soluble fms-like tyrosine kinase 1 (sFlt1), placental growth factor (PlGF) and soluble endoglin (sEng) in FINNPEC case-control cohort. The participants were further divided into subgroups based on parity and onset of the disease. Recommended cut-off values in aid of pre-eclampsia (PE) prediction and diagnosis were also tested.

First trimester serum samples were available from 221 women who later developed PE and 239 women who did not develop PE. Second/third trimester serum samples were available from 175 PE and 55 non-PE women. sFlt-1 and PlGF were measured electro-chemiluminescence immunoassays and sEng by ELISA.

In all timepoints PlGF, endoglin and the sFlt-1/PlGF ratio were increased in the PE group compared to the non-PE group. The serum concentrations of sFlt-1 were increased only at second/third trimester in PE women. Higher concentrations of s-Flt1, endoglin and higher sFlt/PlGF ratio were found at the third trimester in primiparous women compared to multiparous women. Primiparous PE women also had lower concentrations of PlGF at the third trimester. The proportion of women exceeding all cut-offs of the sFlt-1/PlGF ratio (≥33, ≥38, ≥85 and ≥110) was greater in the PE group, but there were also pre-eclamptic women who met rule-out cut-off or did not meet rule-in cut-off.

Primiparous pregnancies have more anti-angiogenic profile during second/third trimester compared with multiparous pregnancies. Our findings also suggest that certain maternal characteristics, e.g. BMI, smoking and pre-existing diseases, should be taken into account when different sFlt-1/PlGF ratio cut-offs are utilized.