As the corresponding author recognized completely normal neonate, whose Apgar score was 9, after appearances of 3 connected typical late decelerations, despite the outcome must be ominous in past reports of late deceleration . while frequently repeated late decelerations appeared in 50 minutes were followed by the Apgar score 3 in severe asphyxia, loss of baseline variability followed by severe brain damage. In addition in a definition, a late deceleration must repeat for more than 15 minutes before the definition.
Thus, late deceleration was ominous not by late appearance of deceleration, but frequently repeated FHR decelerations, thus, we understood the process of fetal damage, because the vagal nerve center located in medulla oblongata was stimulated and excited by the hypoxia, then develops FHR bradycardia and FHR deceleration as well as continuous fetal bradycardia depending on the duration of hypoxia, namely, FHR deceleration was a hypoxic area, thus, repeated decelerations means repeated hypoxia, and repeated hypoxia is effective to damage fetus in the repeated decelerations, thus, novel Hypoxia Index was the sum of FHR deceleration durations (min), divided by the lowest FHR (bpm) because it meant the intensity of hypoxia, and multiplied by 100 to keep the index an integer. Six cases of cerebral palsy and 16 noncerebral palsy cases, who were diagnosed in pediatric clinic were collected, and their hypoxia indices were calculated in the FHR curves recorded in intrapartum fetal monitoring and preserved in obstetric ward in retrospective studies.
The hypoxia index of all 6 cerebral palsy  cases were 25 or more, while the hypoxia index of all 16 non cerebral palsy cases were 24 or less, and there was significant difference of cerebral palsy cases in high and low hypoxia index groups. The P of Chi2 test was almost zero (Table1) (Figure 1). Infantile
cerebral palsy caused by intrapartum damage is prevented when the hypoxia index is 24 or less. Parturient woman is requested to take lateral posture when a FHR deceleration appears in fetal monitoring to prevent further deceleration to prevent high hypoxia index.
A mathematical FHR score is calculated in the parts FHR deceleration in every 5 minutes of fetal monitoring, which is calculated by the sum of 11 deceleration parts evaluation scores of FHR in 5min. The evaluation scores were calculated by the percentage of lower Apgar score than 7 in each deceleration parts of FHR. Apgar score and umbilical cord blood pH were calculated with regression equations of FHR score and Apgar score & umbilical cord blood pH (UApH) [3,4].
PHR score, Apgar score & UApH are predicted even in the
first stage of labor, thus, early caesarean delivery is able to be
selected even in the1st stage of labor.
A truly pathologic sinusoidal FHR caused by severe fetal
anemia or heavy asphyxia should be separated from physiologic
sinusoidal FHR, which is fully favorable, while its wave form is
close to pathologic one. Physiologic favorable one is caused by
cyclic fetal mouthing or respiratory movements and separated
from pathologic one when it is recorded by actocardiogram
(ACG) but not by cardiotocogram (CTG). Pathologic sinusoidal
one is diagnosed by frequency spectrum analysis, namely, La/Ta
ratio is more than 39% and at the same time PPSD is 300 or more
in frequency spectrum analysis . True pathological sinusoidal
FHR fetus should receive early caesarean delivery, followed by
neonatal blood transfusion, if it is caused by fetal anemia.
Artificial neural network computer was able to diagnose
the probability to be normal, suspicious or abnormal outcome
of fetus, however, the result is the same as FHR score, thus, it
is not included in clinical FHR diagnostic computer. The ratio of
Acceleration duration/movement Burst duration (A/B) ratio,
namely, the Apgar score was less than 7 when A/B ratio was less
than 1, however, the result was overlapped to the results of FHR
score, thus, it did not included in common computerized FHR
The hypoxia index was composed on the facts of vague
outcome of scarce and frequently repeated late decelerations.
Although “Cerebral palsy” is a summarized disease name , the
cerebral palsy and normal cases were grouped also according
to the facts. Two groups of hypoxia index were composed of
“cerebral palsy” and “no cerebral palsy” cases, which were
suitable to separate two groups separated by a clear numeric
threshold, which was severely requested to estimate the outcome
of fetal monitoring. However, statistic technique was established,
namely, the threshold is hypoxia index, which is similar to Apgar
score, which is a single numeric score. The target is a disease
or one simple numeric data, for example estimate Apgar scoe or
umb pH by the hypoxia index, and so on. It was problem to decide
fetal outcome by observers visual classification. The method
allowed observers difference and vague results. That was FHR
pattern classification after Hon  till present in 60 years.
Numeric decision was made by Maeda’s FHR score which
predicted Apgar and UApH [3,4]. Frequency spectrum analysis
decided pathologic sinusoidal FHR . FHR score, hypoxia index
and FHR frequency spectrum will be sufficient at present. Such
simple computer composed 3 parameters is constructing. Past
pattern diagnosis prevented severe asphyxia and fetal demise,
but not cerebral palsy, which are possible by the hypoxia index, if
it is tried to prevent severe asphyxia. Although the FHR pattern
prevented fetal demise, but neither Apgar score nor UApH, which
is done by FHR score . The regression equation is useful. Every
diagnosis should be done by three parameters. Even deceleration
removal is recommended by lateral posture of parturient woman.
The new field is wide in update fetal monitoring.
New field is open in FHR monitoring by numerical criteria
to prevent infantile cerebral palsy with hypoxia index and other
update mathematical analysis, instead of subjective fetal outcome
estimation with FHR deceleration pattern classification .It is
suitable to introduce mathematical analysis into computerized
studies, although it is able to be studied with manual calculation.