New transducer for detecting fetal heart sounds: use of compliance matching for maximum sound transfer.
D001794:Blood Pressure; D004562:Electrocardiography; D005260:Female; D005318:Fetal Heart / Q000502:physiology*; D006326:Heart Auscultation / Q000295:instrumentation*; D006339:Heart Rate; D006801:Humans; D011247:Pregnancy; D014159:Transducers