This is potentially a double-edged sword, according to experts: Although the test might pick up more curable conditions earlier, some worry that it may lead to more abortions.
American scientists were able to map the baby's genetic code form tiny traces of free-floating DNA in blood from the baby's mother, who was 18 weeks pregnant.
They were also able to pinpoint if the mutations came from the mother or father's side.
If the technique is refined and the technology becomes inexpensive, as many experts predict, this type of prenatal testing could allow doctors to screen unborn babies for 3,500 genetic disorders by taking a blood sample from the mother and a swab of saliva from the father.
Now, the only genetic disorder routinely testing is Down Syndrome.
"On the positive side, picking up genetic problems early may lead to better treatments, sometimes while the baby is still a fetus, sometimes right after birth and that might prevent complications," said KNBC medical reporter Dr. Bruce Hensel.
"It might give peace of mind if parents don't find problems. On the other hand, it could lead to dilemmas - what do you do about them can you treat them, might it lead to more abortions?" Hensel added.
The genetic predictions in the study were confirmed by analyzing umbilical cord blood collected at the baby's birth.
The test is not being used yet, and experts said the methods will have to refined before the screenings are widely used.
"This is only preliminary. We'll need to see if the test is consistently accurate, because we're looking at the mother's blood, not the baby's, and it might not be 100 percent accurate," Hensel said. "You don't want to find potential genetic disorders that don't pan out to be a real problem at all."
Scientists contend that this type of testing is not as dangerous as some of the testing done with the mother and the womb.