tour baseline risk for trisomy depends on the maternal and gestational age as well as your previous history of trisomy.
     
  Your baseline risk is then modified sequentially with different markers.
 
 

Maternal age /
previous history

  
   
  Your baseline risk is then modified sequentially with different markers.
   

Echographic :
Nuchal translucency

Nuchal translucency is an echographic marker which is performed between 11.3 and 13.6 weeks of gestational age. It is an important marker for the Down syndrome.
 

Maternal serum

Markers

First trimester :

  • Free hCG
  • PAPP-A

Second trimester :

  • Free hCG
  • Inhibine A
  • Estrion
  • Alpha-fetoprotein