These findings led us to indication of the chorionic villi sampling in both fetuses, but the results were normal (46, XX and 46, XY). At 19 weeks another ultrasonography was performed. This examination found normal fetus A, but the fetus B was small for gestational age and exhibited a few cardiac anomalies.
Images 10, 11 and 12: 19 weeks; a large overriding aorta of the fetus B can be seen.