Automated electrochemiluminescence immunoassay for serum PlGF levels in women with singleton pregnancy at 9-13 weeks of gestation predicts preterm preeclampsia: a retrospective cohort study

Abstract

Our aims were to obtain the gestational-age-specific median of common logarithmic placental growth factor (PlGF) values in the first trimester in women with a singleton pregnancy in order to generate the gestational-age-specific multiple of the median (MoM) of log₁₀PlGF at 9-13 weeks of gestation, to evaluate screening parameters of MoM of log₁₀PlGF at 9-13 weeks of gestation to predict preterm preeclampsia (PE), and to construct an appropriate prediction model for preterm PE using minimum risk factors in multivariable logistic regression analyses in a retrospective sub-cohort study. Preterm PE occurred in 2.9% (20/700), and PE in 5.1% (36/700). Serum PlGF levels were measured using Elecsys PlGF^®. MoMs of log₁₀PlGF at 9-13 weeks of gestation in Japanese women with a singleton pregnancy followed a normal distribution. We determined the appropriate cut-off value of MoM of log₁₀PlGF to predict preterm PE at around a10% false-positive rate (0.854). The MoM of log₁₀PlGF < 0.854 yielded sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio (95% confidence interval [CI]), and negative likelihood ratio (95% CI) of 55.0%, 91.9%, 17.5%, 98.5%, 6.79 (4.22-10.91), and 0.49 (0.30-0.80), respectively. The combination of MoM of log₁₀PlGF and presence of either chronic hypertension or history of PE/gestational hypertension (GH) yielded sensitivity and specificity of 80.0 and 85.7%, respectively, to predict preterm PE. In conclusion, the automated electrochemiluminescence immunoassay for serum PlGF levels in women with singleton pregnancy at 9-13 weeks of gestation may be useful to predict preterm PE.

Keywords: Multivariable model; Placental growth factor; Prediction; Preterm preeclampsia; Term preeclampsia.