A decrease in fetal pH during the second stage of labour, when conducted in the dorsal position.
D001769:Blood; D005260:Female; D005333:Fetus; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007743:Labor, Obstetric; D011187:Posture; D011247:Pregnancy; D012535:Scalp / Q000098:blood supply; D013997:Time Factors; D014469:Umbilical Arteries