title: Quantification of fetal heart beat-to-beat interval differences.
mesh_terms: D003201:Computers; D036861:Delivery, Obstetric; D004562:Electrocardiography; D005260:Female; D005318:Fetal Heart / Q000294:innervation / Q000502:physiology*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007743:Labor, Obstetric; D008431:Maternal-Fetal Exchange; D008433:Mathematics; D008614:Meperidine / Q000494:pharmacology; D010275:Parasympathetic Nervous System / Q000502:physiology*; D011247:Pregnancy; D011398:Promethazine / Q000494:pharmacology; D013268:Stimulation, Chemical; D013564:Sympathetic Nervous System / Q000502:physiology*
chemical_list: D008614:Meperidine; D011398:Promethazine