Maternal serum placental growth factor (PIGF) in small for gestational age pregnancy at 11+0 to 13+6 weeks of gestation

Objective To investigate the pathogenesis of pregnancies delivering small for gestational age (SGA) neonates by examining biochemical and Doppler indices of placental development during the first trimester of pregnancy. Method The concentration of placental growth factor (PIGF) at 11(+0)-13(+6) weeks was measure in 296 cases, which delivered SGA neonates, and 609 controls. The newborn was considered to be SGA if the birth weight was less than the fifth percentile after correction for gestation at delivery and sex, maternal racial origin, weight, height and parity. The distributions of uterine artery pulsatility index (PI), PIGF and PAPP-A, expressed in multiples of the median (MoM), in the control and SGA groups were compared. Logistic regression analysis was used to determine if significant contribution is provided by maternal factors. PIGF, PAPP-A and uterine artery PI in predicting SGA. Results The median PIGF (0.900 MoM) and PAPP-A (0.778 MoM) were lower and uterine artery PI was higher (1.087 MoM) in the SGA group than in the controls (PIGF: 0.991 MoM, PAPP-A: 1.070 MoM; urine artery PI: 1.030 MoM). In the SGA group there was significant association between PIGF and PAPP-A (r = 0.368, p < 0.0001) and uterine artery PI (r = 0.191, p = 0.001). Significant contributions for the prediction of SGA were provided by maternal factors. PIGF and PAPP-A and with combined screening the detection rate was 27% at a false-positive rate of 5%. Conclusion Birth weight is predetermined by placental development during the first trimester of pregnancy. Copyright (c) 2008 John Wiley & Sons, Ltd.