-
Sonographic screening for trisomy 13 at 11 to 13(+6) weeks of gestation.
Papageorghiou AT, Avgidou K, Spencer K, Nix B, Nicolaides KH.
Am J Obstet Gynecol 2006;194:397-401. -
Cell-free DNA levels in pregnancies at risk of sickle-cell disease and significant ethnic variation.
Gerovassili A, Nicolaides KH, Thein SL, Rees DC.
Br J Haematol 2006;135:738-41.