Prognostic value of sFlt-1 and PlGF in the diagnosis of abnormally deep placental invasion

Abstract

BACKGROUND: Placental adhesive disorder is associated with a high risk of massive bleeding during pregnancy and caesarean delivery. Abnormal trophoblast invasion and pathological hypervascularization detected in these patients may be due to the imbalance of angiogenic factors such as PlGF and sFlt-1, which makes their study an important area of scientific and clinical practice. AIM: The aim of this study was to evaluate sFlt-1 and PlGF levels in women with placenta accrete spectrum and to compare the data with the results in women with normal pregnancy. MATERIALS AND METHODS: This case-control study included 71 pregnant women in the third trimester of pregnancy. The main group (n = 32) consisted of patients with prenatally diagnosed placenta previa and abnormally invasive placenta; the control group (n = 39) included patients with normal pregnancy. In the study groups, the levels of sFlt-1 and PlGF were determined, with ultrasound and MRI characteristics evaluated. Statistical analysis was performed using IBM SPSS Statistics 26.0. RESULTS: Serum sFlt-1 and PlGF levels in the study group differed as compared to controls. In women with placenta accreta spectrum, the median sFlt-1 level was 2886.0 [2175.04127.0] pg/ml vs. control: 1890.0 [1807.02205.0] pg/ml (р 0.001); the median PlGF level was 233.5 [171.4460.5] pg/ml vs. control: 880.9 [746.61210.0] pg/ml (p 0.001). A correlation was revealed between the angiogenic factor levels and the degree of pathological hypervascularization and collaterization according to MRI data. When comparing the probability of abnormally invasive placenta (PAS Grades 2 or 3) and the sFlt-1/PlGF ratio, an ROC curve was obtained with the AUC of 0.74 0.13 (95% CI: 0.481.0; p = 0.021). CONCLUSIONS: Patients with placental adhesive disorder had increased sFlt-1 levels and decreased PlGF levels compared to patients with normal pregnancy. The above levels correlated with the degree of pathological hypervascularization and collaterization detected by MRI. A prognostic model has been obtained, according to which the threshold value of the sFlt-1/PlGF ratio of 4.22 allows for distinguishing patients with deep placental invasion (PAS Grades 2 or 3).