During pregnancy, small fragments of the baby’s DNA circulate in the mother’s bloodstream. A noninvasive prenatal paternity test isolates those fragments from a maternal blood sample and compares them with a cheek swab from the alleged father.
Because the sample comes from the mother’s arm, not from inside the womb, the procedure avoids the invasive sampling used by older prenatal methods, though a standard blood draw carries the usual minor risks of any blood draw. Many expecting parents find that knowing earlier brings calm, clearer planning, and fewer difficult conversations later.