title: Sex variation at the time of sonographic appearance of the proximal tibial epiphyseal ossification center.
abstract: The time of sonographic appearance of the proximal tibial epiphyseal ossification center and its sexual variation was assessed in 659 normal pregnancies. Proximal tibial center appears between 34-37 weeks gestation. In female fetuses, it appears between 34-35 weeks and in males, between 35-36 weeks (P < 0.001). There was a tendency of female proximal tibial center appearance to precede male appearance, by approximately one week. This difference, however, didn't show statistical significance.
authors.affiliation: Clinica Paulista de Assistência à Mulher (CLIPAM, São Paulo Clinic for Women's Care), Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Nazário
authors.forename: C I
authors.initials: CI
authors.lastname: Tanaka
authors.forename: R M
authors.initials: RM
authors.lastname: Santana
authors.forename: Y
authors.initials: Y
authors.lastname: Juliano
mesh_terms: D005314:Embryonic and Fetal Development; D004838:Epiphyses / Q000000981:diagnostic imaging / Q000196:embryology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D008297:Male; D011247:Pregnancy; D012727:Sex Characteristics; D013977:Tibia / Q000000981:diagnostic imaging / Q000196:embryology*; D014463:Ultrasonography