ACOG Practice Bulletin No. 101: Ultrasonography in pregnancy.
D000013:Congenital Abnormalities / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000000981:diagnostic imaging; D011261:Pregnancy Trimester, First; D016216:Ultrasonography, Prenatal