I'm not 100% sure what "before the test" means, but I guess it's just factoring in my age, race, etc., and the baby's age. And, I guess "after the test" also factors in the amount of fluid at the base of the neck (from the ultrasound) and the blood results.
Before the test, our risk of Downs syndrome was 1 in 590. After the test, our risk is 1 in 3,500.
Before the test, our risk of Trisomy 18 was 1 in 2,000. After the test, our risk is 1 in 10,000.
It would appear, then, that we have a healthy baby!!!!