Patent ID: 8876714

Claim:
A ultrasound system comprising: an ultrasound transducer; and a processor electrically coupled to the ultrasound transducer and configured to determine nuchal translucency values for each of a first fetus of twin fetuses and a second fetus of twin fetuses and provide a risk of a chromosomal abnormality in each of the first fetus and the second fetus of twin fetuses by determining a first, second and third determined likelihood ratio using the nuchal translucency values and using a between-fetus nuchal translucency correlation, in which the processor is configured to determine the first likelihood ratio based on the first fetus including the chromosomal abnormality and a second fetus being normal, is configured to determine the second likelihood ratio based on the first fetus being normal and the second fetus including the chromosomal abnormality and is configured to determine the third likelihood ratio based on the first fetus including the chromosomal abnormality and the second fetus including the chromosomal abnormality.