Researchers at Stanford University have studied the DNA of a fetus using only a blood sample from its mother.
All pregnant women have their baby's cells circulating in their blood.
In the new study, researchers isolated cells containing fetal DNA from a blood sample given by the mother. They were able to find rare genetic diseases not able to be identified before.
They didn't need a DNA sample from the father to get the results.
Experts are excited this new test will eliminate the need for invasive genetic testing, like an amniocentesis.
So far, two pregnant women have undergone the test. If verified in larger trials, experts said this test could help doctors treat genetic diseases before or shortly after a baby is born.