title: Principal results from the use of ultrasonic diagnosis in obstetrics.
mesh_terms: D004452:Echocardiography; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis; D005333:Fetus; D006801:Humans; D007746:Labor Presentation; D010388:Pelvis / Q000033:anatomy & histology; D010920:Placenta; D011247:Pregnancy; D011272:Pregnancy, Multiple; D014465:Ultrasonics / Q000295:instrumentation; D014463:Ultrasonography