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Serum CA125 at 11-14 weeks of gestation in women with morphologically normal ovaries.
Aslam N, Ong C, Woelfer B, Nicolaides K, Jurkovic D.
BJOG 2000;107:689-90. -
Maternal serum inhibin-A and free beta-hCG concentrations in trisomy 21 pregnancies at 10-14 weeks of gestation.
Noble PL, Wallace EM, Snijders RJ, Groome NP, Nicolaides KH.
BJOG 1997;104:367-71.