Sex-determining region Y levels in maternal plasma: Evaluation in abnormal pregnancy

Aim: A number of studies for the measurement of cell‐free fetal DNA in maternal blood have been reported; however, their clinical significance has remained unclear. We proposed to clarify the relationship between fetal DNA levels and obstetrical disorders. Methods: One hundred and eighty‐five cases of normal pregnancy, ranging from 8 to 40 weeks’ gestation, and 70 cases of abnormal pregnancy were included. SRY levels in maternal plasma were quantified with a real‐time quantitative polymerase chain reaction. Results: Sex‐determining region Y (SRY) levels and the number of patients with positive levels peaked at 33–36 weeks in normal pregnancy. The SRY levels in threatened abortion (11.6 ± 4.8 copies/mL to 0 ± 0, P