Noninvasive fetal sex determination by analysis of cell-free fetal DNA in maternal capillary blood obtained by fingertip puncture.

Abstract

What's already known about this topic? Noninvasive fetal sex determination searches for Y‐chromosome sequences in maternal plasma isolated from venous blood drawn by venipuncture to indicate fetal sex in the first trimester of pregnancy. Capillary blood collection is much less invasive than venipuncture, thereby offering the possibility of sampling in geographical areas where there is no phlebotomist present. What does this study add? Fetal DNA is present in maternal capillary blood allowing for noninvasive fetal sex determination. Exogenous male DNA may be present, and detectable, on the fingertips of pregnant women. The elimination of the exogenous male DNA is critical for a reliable fetal sex determination using maternal capillary blood. A diluted buffered sodium hypochlorite (0.5%‐1%) can be used to eliminate exogenous male DNA from the fingertips of pregnant women.