title: Constant soft tissue distance model in pregnancy.
authors.affiliation: Division of Radiological Physics, University of Michigan Hospitals, Ann Arbor 48109-0553.
authors.forename: P L
authors.initials: PL
authors.lastname: Carson
authors.forename: J M
authors.initials: JM
authors.lastname: Rubin
authors.forename: E H
authors.initials: EH
authors.lastname: Chiang
mesh_terms: D000649:Amniocentesis; D001835:Body Weight; D005260:Female; D006801:Humans; D008954:Models, Biological; D011247:Pregnancy; D011296:Prenatal Diagnosis; D014159:Transducers; D014463:Ultrasonography