Sinusoidal fetal heart rate and butorphanol administration.
D000773:Anesthesia, Obstetrical / Q000009:adverse effects*; D002077:Butorphanol / Q000009:adverse effects*; D005260:Female; D005318:Fetal Heart / Q000187:drug effects* / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007231:Infant, Newborn; D009019:Morphinans / Q000009:adverse effects*; D011247:Pregnancy
D009019:Morphinans; D002077:Butorphanol