title: Prenatal observation of fetal defecation using four-dimensional ultrasonography.
authors.forename: C L
authors.initials: CL
authors.lastname: Ramón y Cajal
authors.forename: R O
authors.initials: RO
authors.lastname: Martínez
mesh_terms: D001003:Anal Canal / Q000000981:diagnostic imaging; D003672:Defecation / Q000502:physiology; D005260:Female; D005333:Fetus / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D016216:Ultrasonography, Prenatal