title: A question of angle of view.
authors: Y
authors: Y
authors: Paltieli
authors: J
authors: J
authors: Nizard
mesh_terms: D005260:Female; D006257:Head / Q000000981:diagnostic imaging*; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology*; D011247:Pregnancy; D014463:Ultrasonography