title: Time--an important variable in normal delivery.
mesh_terms: D001237:Asphyxia; D001769:Blood; D002245:Carbon Dioxide / Q000097:blood; D036861:Delivery, Obstetric; D004841:Episiotomy; D005260:Female; D005315:Fetal Diseases; D005333:Fetus / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009772:Obstetrical Forceps; D010100:Oxygen / Q000097:blood; D011247:Pregnancy; D013997:Time Factors; D014469:Umbilical Arteries; D014470:Umbilical Cord; D014471:Umbilical Veins
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen