From: Prenatal diagnosis of 4953 pregnant women with indications for genetic amniocentesis in Northeast China
Cases, n
DS≧1:270 & ES≧1:350, n
DS 1:270~1:500 & ES 1:350~1:500, n
DS and ES 1:500~1:1000, n
Positive serological
102
82
16
4
Positive NIPT
20
14
2