Beginning around just 5 weeks gestation, tiny fragments of DNA from a developing embryo travel through the placenta and into the mother’s bloodstream. If the embryo will be baby boy, this DNA will carry a Y chromosome. If the embryo will be a baby girl, the DNA will not have a Y chromosome.
Our scientists carefully analyze the mother’s blood sample with the most advanced quantitative PCR technology to look for this Y chromosome. The technology used is so sensitive, it’s able to determine if the baby is a boy or a girl as early as 6 weeks into pregnancy.