Prospective Analysis of Placenta Growth Factor (PlGF) Concentrations in the Plasma of Women with Normal Pregnancy and Pregnancies Complicated by Preeclampsia

Abstract

The aim of this study was to analyze if levels of plasma PlGF in the second half of pregnancy have predictive value for the identification of women destined to develop preeclampsia or another complication of pregnancy. A bank of 1.543 randomly collected plasma samples (22-29 weeks of gestation) was established and PlGF concentrations were quantitated in a prospective longitudinal study in all pregnant women who developed a complication of pregnancy in late gestation (177 of 1.543) and the same number of gestational age matched pregnancies with normal outcome. Plasma PlGF levels in pregnant women rise steadily throughout pregnancy from the level of nonpregnant women (< 50 pg/mL) to levels exceeding 500 pg/mL after 30 weeks of gestation. Just 7.3% of pregnant women with normal outcome of pregnancy had PlGF levels of less than 200 pg/mL beyond 22 weeks of gestation (3.7% beyond 25 weeks of gestation). The rise in plasma PlGF in the second half of pregnancy was significantly attenuated in pregnancies that were complicated by preeclampsia in late gestation. Of all women who developed preeclampsia, 27.3% (12 of 44) had plasma PlGF levels below 200 pg/mL. The attenuation of the rise in plasma PlGF was not evident in other complications of pregnancy (transient hypertension, fetal retardation, pregnancy diabetes, premature contractions, proteinuria without hypertension, infections during pregnancy). The rise in plasma PlGF levels observed in normal pregnancies is significantly attenuated in pregnancies complicated by preeclampsia. Yet, due to the low sensitivity and specificity, plasma PlGF levels in the second half of pregnancy have no predictive value for the identification of individual women destined to develop preeclampsia.