Levels of maternal serum angiogenic factors in third-trimester normal pregnancies: reference ranges, influence of maternal and pregnancy factors and fetoplacental Doppler indices.

Aim: To establish normal ranges of maternal placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and sFlt-1/PlGF ratio at 32-41 weeks' gestation and to evaluate the influence of maternal characteristics, and of fetoplacental Doppler.

Material And Methods: Serum levels of PlGF, sFlt-1 and sFlt-1/PlGF ratio were measured in 300 noncomplicated pregnancies (30 at each gestational week between 32 and 41). Quantile regression analysis was used to derive gestational age (GA)-adjusted normal ranges, and to account for characteristics that might influence serum levels.