Value of second trimester maternal serum sFlt-1, PlGF and their ratio in the prediction of preeclampsia

Abstract

To study the value of second trimester maternal serum soluble Fms-like tyrosine kinase 1 (sFlt-1), placenta grouth factor (PlGF) and their ratio in the prediction of preeclampsia. In this nested case-control study, we collected second trimester maternal serum samples at 15-20 weeks and 24-28 weeks of gestation from those who developed gestational hypertensive disorders. Maternal serum sFlt-1 and PlGF were measured by electrochemiluminescence immunoassay on an automated platform. The value of sFlt-1, PlGF and their ratio were compared between gestational hypertensive group and the control group. Totally 41 patients with preeclampsia, 44 patients with gestational hypertension and 88 women with normal pregnancy outcomes were included in this study. There was no difference of age, gravidity, parity and preconception body mass index (BMI) between these three groups (P > 0.05) .Gestational week at delivery and neonatal birth weight were different between preeclampsia group and the control group (P < 0.01). The mean value of sFlt-1, PlGF and sFlt-1/PlGF ratio was (1 658 ± 488) µg/L, (141 ± 80) µg/L and 17 ± 9 in preeclampsia group, (1 945 ± 575) µg/L, (143 ± 52) µg/L and 15 ± 6 in gestational hypertension group, and (2 084 ± 741) µg/L, (65 ± 58) µg/L and 16 ± 9 in the control group at 15-20 weeks of gestation. There was no difference of sFlt-1, PlGF value and their ratio among the three groups at 15-20 weeks of gestation (P > 0.05) . The median value of sFlt-1, PlGF and sFlt-1/PlGF ratio were 8 525 µg/L, 35 µg/L and 398.0 in preeclampsia group, 905 µg/L, 336 µg/L and 2.7 in gestational hypertension group, 1 028 µg/L, 477 µg/L and 2.3 in the control group at 24-28 weeks of gestation. The value of sFlt-1, PlGF and their ratio was significantly different between preeclampsia group and the control group at 24-28 weeks of gestation (P < 0.01) . PlGF value was different between gestational hypertension group and the control group (P < 0.01) . The sensitivity and specificity of serum sFlt-1, PlGF and sFlt-1/PlGF ratio at 24-28 weeks of gestation to predict preeclampsia were 93% and 99% for sFlt-1 (cut off value 2 500 µg/L), 92% and 77% for PlGF (cut off value 270 µg/L) , 89% and 99% for sFlt-1/PlGF ratio (cut off value 11) . The value of sFlt-1, PlGF and their ratio at 24-28 weeks of gestation was significantly changed before clinical onset of preeclampsia.Use these serum indicators to predict preeclampsia will hopefully provide objective evidence for the management of patients who will develop preeclampsia later.