The hypoxia index covers roles of all decelerations and will reduce cerebral palsy

It was strange that fetal outcome was vigorous in 3 late decelerations, but ominous when it repeated. It was thought that FHR decelerations expresses hypoxia, because the heart rate was fully parallel to rabbit PaO2, if it is below 50mmHg, and human fetal PaO2 is 50mmHg or less. Thus, a hypoxia index (HI), that is hypoxic nature, was sum of deceleration duration (min) divided by the lowest nadir FHR (bpm), and multiplied by 100. Its calculation is easy by computer, though possible by manual calculation. HI has regression equation with Apgar score, and Apgar score was high in 2 to 3 late decelerations (LD), while HI was high and Apgar score was low in repeared LDs, solving the LD discrepancy. Although no particular role is expected by LD pattern, hypoxic effect is estimated in repeated large decelerations and deep bradycardia, namely, numerical analysis is possible in the deceleration and continuous bradycardia.