Yields of aneuploidy and correlation with ultrasonographic
findings
Among all isolated ultrasonographic anomalies, the fetal hydrops had the
highest yield of aneuploidy (34.85%), followed by cystic hygroma
(24.76%), and abdominal wall defect (13.71%) (Table 2). Among all
isolated soft markers, the increased nuchal translucency had the highest
yield of aneuploidy (12.43%), followed by absent or hypoplastic nasal
bone (6.63%) and thickened nuchal fold (5.47%)(Table 3).
We observed that the yields of aneuploidy increased with the number of
anomalies or soft markers. When fetuses presented with multiple
ultrasonographic anomalies or soft markers, the yields of aneuploidy
increased from 5.05% (597/11,818) to 28.83% (79/274) and 6.98%
(1,107/15,856) to 16.81% (20/119), respectively. Specifically, the
yield of aneuploidy in fetuses with both fetal hydrops and cystic
hygroma was up to 64.94% (50/77) (Table S2). The yield of aneuploidies
in fetuses with increased nuchal translucency and absent or hypoplastic
nasal bone was as high as 61.63% (53/86) (Table S3).
Overall, three aneuploidies, including trisomy 18, 45,X syndrome, and
trisomy 13,
were significantly associated with ultrasonographic anomalies, while
trisomy 21 was significantly associated with soft markers (Figure S2A ).
Specifically, trisomy 21 significantly associated with soft markers such
as absent or hypoplastic nasal bone, increased nuchal translucency, and
thickened nuchal fold, as well as with
ultrasonographic anomalies, including cystic hygroma and fetal hydrops
(Figure S2B). Trisomy 18 was significantly associated with soft markers
and ultrasonographic anomalies, presenting in three types of soft
markers (single umbilical artery, increased
nuchal translucency, and choroid plexus cysts) and ultrasonographic
anomalies (fetal
hydrops, cystic hygroma, and abdominal wall defect). Both 47,XXY and
47,XYY syndromes tended to occur with normal ultrasonographic findings
and showed no significant association with soft markers and
ultrasonographic anomalies. In addition, 45,X syndrome was significantly
associated with increased nuchal translucency, fetal hydrops, and cystic
hygroma, while trisomy 13 was significantly associated with abdominal
wall defect and increased nuchal translucency (Figure S2B).