Considerations When Ordering Non-invasive Prenatal Screening (NIPS)

NIPS generally relies on blood testing from the mother to reveal information from circulating cell-free DNA (cfDNA) from the placenta, which can be identified in the maternal plasma from five weeks after conception. CfDNA is released into the blood stream as small DNA fragments of about 150-200 base pairs. About 2 percent to 20 percent of the total cell-free DNA in the maternal blood is actually from the placenta, and, importantly, this placental DNA is cleared from circulation within hours following birth.