An FHR algorithm to predict fetal asphyxia

We have addressed this question. A matched case control study was conducted in term pregnancies to demonstrate that a threshold of FHR patterns can be defined and that intermediate patterns of FHR can be determined for intra-partum fetal asphyxia [29]. The FHR records were scored for each FHR variable for six 10-min cycles in each hour.

FHR variables with an independent association with fetal asphyxia (i.e. umbilical artery base deficit greater than 16 mmol/l at delivery) in this study were absent as well as minimal baseline variability and late and prolonged decelerations. Three FHR patterns were defined based on the presence of these four FHR variables in six 10-min cycles in 1 h. The patterns proposed as an algorithm for the interpretation of electronic FHR records are outlined in Table 8.3.

A number of relevant observations emerged from this study. The sensitivity of predictive and potentially predictive FHR patterns was good identifying 75% of the cases with fetal asphyxia. In the 25% of cases not identified, the fetal asphyxia was mild. The positive predictive value of a predictive FHR pattern that occurred in 17% of the cases was very good. However, in these cases the fetal asphyxia was already moderate or severe. The positive predictive value of potentially predictive FHR patterns, 10 and 5% respectively, was very poor. These potentially predictive patterns accounted for over 50% of the fetal asphyxia ranging from mild to moderate in degree.

The potentially predictive patterns unless clarified by supplementary tests represent a dilemma for the clinician. The pattern can be ignored and in ten cases, fetal asphyxia will not be present in nine; however, in one case, fetal asphyxia accounting for at least 50% of asphyxia will be present and continue. On the other hand, the pattern can serve as an indication for intervention leading to an unnecessary intervention in nine out of ten cases.

Table 8.3 Predictive and potentially predictive fetal heart rate patterns for intrapartum fetal asphyxia



variability (cycles/h)

late/prolonged (cycles/h)


Absent > 1


> 2

Potentially predictive #1

Minimal > 2




Minimal > 2



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Pregnancy Diet Plan

Pregnancy Diet Plan

The first trimester is very important for the mother and the baby. For most women it is common to find out about their pregnancy after they have missed their menstrual cycle. Since, not all women note their menstrual cycle and dates of intercourse, it may cause slight confusion about the exact date of conception. That is why most women find out that they are pregnant only after one month of pregnancy.

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