Prenatal diagnosis with chromosome microarray and pregnancy outcomes of fetuses with biliary tract system abnormalities.

An isolated BTS abnormality is not an indication for invasive prenatal chromosomal analysis. When combined with other ultrasonographic abnormalities, prenatal CMA should be provided. When a small or nonvisualized gallbladder is found prenatally, ultrasonography is limited in the differential diagnosis of congenital biliary atresia.