Giacomello's observation and nuchal cords.
Collins
J
J
D001946:Breech Presentation; D005260:Female; D006801:Humans; D010920:Placenta / Q000000981:diagnostic imaging*; D010922:Placenta Diseases / Q000000981:diagnostic imaging*; D011247:Pregnancy; D014102:Torsion Abnormality / Q000000981:diagnostic imaging; D014463:Ultrasonography