-
First-Trimester Screening for Trisomy 21 with Adjustment for Biochemical Results of Previous Pregnancies.
Wright D, Syngelaki A, Birdir C, Bedei I, Nicolaides KH.
Fetal Diagn Ther 2011;30:194-202. -
First-trimester screening for trisomy 21 in singleton pregnancies achieved by assisted reproduction.
Liao AW, Heath V, Kametas N, Spencer K, Nicolaides KH.
Hum Reprod 2001;16:1501-4.