Maternal serum placental growth factor (PlGF) isoforms 1 and 2 at 11-13 weeks' gestation in normal and pathological pregnancies.

OBJECTIVE To compare the maternal serum concentration of placental growth factor-1 (PlGF-1) and PlGF-2 at 11-13 weeks' gestation in normal pregnancies and in those complicated by preeclampsia (PE), delivery of small for gestational age (SGA) neonates and fetal trisomies 21, 18 and 13. METHODS Serum PlGF-1 and PlGF-2 were measured in 270 pathological pregnancies (PE, n = 80; SGA, n = 80; trisomy 21, n = 44; trisomy 18, n = 38; trisomy 13, n = 28) and 590 normal controls. The values were expressed as multiple of the median (MoM) after adjustment for maternal characteristics and corrected for adverse pregnancy outcomes and the median MoM values in each pathological pregnancy were compared to the normal group. RESULTS There were significant contributions to PlGF-1 and PlGF-2 from gestational age, smoking and racial origin. In addition, there were significant contributions to PlGF-1 from parity and method of conception. The median MoM of PlGF-1 and PlGF-2 was significantly decreased in PE (0.783 and 0.916 MoM), SGA (0.891 and 0.851 MoM), trisomy 21 (0.609 and 0.749 MoM), trisomy 18 (0.529 and 0.730 MoM) and trisomy 13 (0.373 and 0.699 MoM). CONCLUSIONS In pathological pregnancies, except SGA, the decrease in serum PlGF-1 at 11-13 weeks' gestation is more marked than the decrease in PlGF-2.