Fetal DNA in maternal circulation of first-trimester spontaneous abortions

Objective: To establish whether fetal DNA can be identified in the maternal circulation in first-trimester spontaneous abortions. Methods: Women with confirmed spontaneous abortions and no histories of pre vious pregnancy were recruited. Peripheral venous blood samples were obtain ed and DNA extracted. Real-time quantitative polymerase chain reaction was done using SRY and beta -actin systems for calculating fetal and total DNA, respectively. Results: Of 25 women, SPY-specific signals were detected in 11 indicating t hat the abortions were male. The remaining 14 were negative for the SRY gen e. Women with positive results were of similar gestational age to those who were negative (mean 68.4 and 69.0 days). Fetal:total DNA ratio was calcula ted for positive samples and ranged from 15.8 to 360.1 x 10(+3). Mean ratio was 99.4 x 10(+3) and median was 67.5 x 10(+3) Conclusion: Fetal DNA is present in the maternal circulation of first-trime ster spontaneous abortions. (C) 2001 by The American College of Obstetricia ns and Gynecologists.