Maternal serum levels of neutrophil gelatinase-associated lipocalin (NGAL), matrix metalloproteinase-9 (MMP-9) and their complex MMP-9/NGAL in pregnancies with preeclampsia and those with a small for gestational age neonate: a longitudinal study.

BACKGROUND: The aim of this study was to determine maternal serum concentrations of neutrophil gelatinase-associated lipocalin (NGAL), matrix metalloproteinase-9 (MMP-9), and MMP-9/NGAL complex longitudinally in pregnancy, in normal pregnancies, in pregnancies that developed preeclampsia and in pregnancies that delivered a small for gestational age infant (SGA). METHODS: Neutrophil gelatinase-associated lipocalin, MMP-9, and MMP-9/NGAL were determined in the first, second, and third trimesters in 33 normal pregnancies, 12 pregnancies complicated by preeclampsia, and 14 pregnancies that delivered a SGA neonate. RESULTS: Median NGAL concentration (ng/mL) in normal pregnancies increased significantly from 12.8 in the first trimester to 25.9 in the second trimester (p = 0,002) and 48.0 (p < 0.0001) in the third trimester. In preeclamptic pregnancies, NGAL was significantly higher, compared with normal pregnancies, in the first (30.9; p = 0.006) and second (44.6; p = 0.015) trimesters. MMP-9 and MMP-9/NGAL complex concentrations in preeclamptic pregnancies did not differ significantly from normal pregnancies in either trimester. Pregnancies with an SGA infant did not have different marker concentrations in either trimester, compared with normal pregnancies. CONCLUSION: Maternal serum NGAL, MMP-9, and MMP-9/NGAL complex concentrations tend to increase during pregnancy in normal and preeclamptic pregnancies. NGAL was significantly elevated in the first and second trimesters, in pregnancies that later developed preeclampsia.