[Prenatal screening for Down's syndrome--moving from the second to the first trimester of pregnancy].
Maymon
R
R
Herman
A
A
Dreazen
C
C
Bukovsky
I
I
Weinraub
Z
Z
D004314:Down Syndrome / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000196:embryology*; D005260:Female; D006801:Humans; D008403:Mass Screening; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis; D016216:Ultrasonography, Prenatal