16 weeks pregnant, down syndrome screening test positive, 1/150 chance that baby might have abnormality. will do amnio. please explain what results mea?

High Risk for Downs: The screening test result means that you have a 1 in 150 chance that your fetus has down syndrome. While this is considered a positive screen, the chance is still less than 1%. Rather than an amino, you might consider a blood test like the maternit-21, which can be done from your blood and is greater than 99% accurate. Discuss this option with your ob.