Uterine artery Doppler and sFlt-1/PlGF ratio: prognostic value in early-onset pre-eclampsia

Objective To evaluate the performance of the mean uterine artery pulsatility index (UtA-PI) and the automated measurement of the soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) ratio for the prognostic assessment of both maternal and perinatal outcomes, and the time-to-delivery interval in early-onset (<= 34+ 0 weeks) pre-eclampsia (PE) cases with attempted expectant management. Methods Fifty-one singleton pregnancies with early-onset PE were enrolled in the study. Mean UtA-PI and sFlt/PlGF ratio were measured at diagnosis. The association of each marker and their combinations with adverse maternal and perinatal outcomes was assessed by univariable comparisons and multivariable logistic regression analysis and time-to-delivery interval by survival analysis. Results Twenty-six (51%) had adverse maternal outcome and 14 (27%) had adverse perinatal outcome. At the time of onset of PE, only gestational age was significantly related to maternal complications. Gestational age at onset, mean UtA-PI and sFlt-1/PlGF ratio were significantly associated with perinatal complications, their combination reaching a sensitivity of 64% with 95% specificity, and an area under the receiver-operating characteristics curve of 0.89 (95% CI, 0.79-0.99). Regarding the time until delivery, 92% (12/13) of cases with sFlt-1/PlGF ratio >655 and 39% (15/38) of cases with a ratio <= 655 delivered within the first 48 h, 8% (1/13) and 19% (7/38), respectively, delivered between 48 h and 7 days and 0% (0/13) and 42% (16/38), respectively, delivered after 7 days. Conclusion Mean UtA-PI and sFlt-1/PlGF ratio in combination with gestational age are useful for the prognostic assessment of perinatal complications at the time of diagnosis of early-onset PE, but this combination has limited value for the prediction of maternal complications. Moreover, sFlt-1/PlGF ratio >655 is closely related to the need to deliver within 48 h. Copyright (C) 2013 ISUOG. Published by John Wiley & Sons Ltd.