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Trisomy 13 detection in the first trimester of pregnancy using a chromosome-selective cell-free DNA analysis method.
Ashoor G, Syngelaki A, Wang E, Struble C, Oliphant A, Song K, Nicolaides KH.
Ultrasound Obstet Gynecol 2013;41:21-5. -
Second-trimester levels of pregnancy-associated plasma protein-A and free beta-hCG in pregnancies with trisomy 13.
Spencer K, Crossley JA, Aitken DA, Nicolaides KH.
Prenat Diagn 2005;25:358-61.