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First trimester maternal serum AFP and total hCG in aneuploidies other than trisomy 21.
Spencer K, Heath V, Flack N, Ong C, Nicolaides KH.
Prenat Diagn 2000;20:635-9. -
First trimester maternal serum free beta human chorionic gonadotrophin and pregnancy associated plasma protein A as predictors of pregnancy complications.
Ong CY, Liao AW, Spencer K, Munim S, Nicolaides KH.
BJOG 2000;107:1265-70.