Quantification of cell free fetal DNA in maternal plasma in normal pregnancies and in pregnancies with placental dysfunction.

Objective: To assess the normal levels of free fetal DNA in maternal plasma through pregnancy compared with those in pregnancies complicated with placental dysfunction manifested by preeclampsia and/or fetal growth restriction.

Study Design: Maternal blood samples from 138 singleton male pregnancies were divided into 3 groups; normal pregnancies (77), preeclampsia (49), and fetal growth restriction (12). Royston and Wright's methods were used to calculate gestational age-related reference limits of free fetal DNA in the 3 groups.