title: Detection of fetal heart activity during early pregnancy by combined B-scan and Doppler examination: a new application.
mesh_terms: D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005313:Fetal Death; D005318:Fetal Heart / Q000502:physiology*; D005865:Gestational Age; D006339:Heart Rate; D006801:Humans; D011247:Pregnancy; D011259:Pregnancy Tests, Immunologic; D011296:Prenatal Diagnosis; D013997:Time Factors; D014463:Ultrasonography