Table 34, GRADE findings for association between categorisation of fetal heart rate traces and adverse neonatal outcomes - Addendum to intrapartum care: care for healthy women and babies

Table 34GRADE findings for association between categorisation of fetal heart rate traces and adverse neonatal outcomes

Quality assessment						Definition of outcome	Stage of labour	Number of babies with defined FHR patterns	Degree of association or number (percentage) of babies with defined outcome	Quality
Number of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Definition of outcome	Stage of labour	Number of babies with defined FHR patterns		Quality
“Pathological” FHR pattern (NICHD classification)
1 study (Hadar 2001)	Cohort	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord artery pH < 7.2 and BD ≥ 12	2nd stage	301	OR 2.86 (95% CI 0.3 to 24.4) P = 0.33	Moderate
“Predictive” FHR pattern^a
1 study (Low 2001)	Case series	Serious²	No serious inconsistency	No serious indirectness	No serious imprecision	Moderate or severe asphyxia (BD > 12 at birth, encephalopathy and cardiovascular, respiratory and renal complications)	NR	23	n = 13 (56%)	Low
“Suspect” FHR pattern^a
1 study (Low 2001)	Case series	Serious²	No serious inconsistency	No serious indirectness	No serious imprecision	Moderate or severe asphyxia (BD > 12 at birth, encephalopathy and cardiovascular, respiratory and renal complications)	NR	23	n = 7 (30%)	Low
“Non-predictive” FHR pattern^a
1 study (Low 2001)	Case series	Serious²	No serious inconsistency	No serious indirectness	No serious imprecision	Moderate or severe asphyxia (BD > 12 at birth, encephalopathy and cardiovascular, respiratory and renal complications)	NR	26	n = 3 (11.5%)	Low
“Abnormal” FHR tracing (compared with normal tracing - NICHD classification)
1 study (Sheiner 2001)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	pH< 7.2 and BD ≥ 12	1st stage	28	OR 3.4 (95% CI 1.3 to 8.7) P = 0.01	Low
Type 0 FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	103	7.24 ± 0.06	Low
Type 1a FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	93	7.24 ± 0.07 P = ns	Very low
Type 1b FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	19	7.15 ± 0.07 P = 0.0001	Low
Type 2a FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	34	7.19 ± 0.06 P = 0.0001	Low
Type 2b FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	13	7.06 ± 0.07 P = 0.0001	Low
Type 3 FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	14	7.09 ± 0.06 P = 0.0001	Low
Type 4 FHR tracing^b
1 study (Cardoso 1995)	Case series	Serious¹	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	2nd stage	15	7.19 ± 0.07 P = 0.01	Low
“Normal” FHR tracing^b
1 study (Gilstrap 1987)	Cohort	Serious³^,⁴	No serious inconsistency	No serious indirectness	No serious imprecision	Umbilical cord arterial pH (mean ± SD)	1st stage	129	7.29 ± 0.6	Very low
Indeterminate FHR pattern (Category II, NICHD classification 2008)
1 study (Sharbaf 2014)	Prospective cohort	Very serious⁵	No serious inconsistency	No serious indirectness	Serious⁶	Umbilical artery pH ≤7.2	“Early labour”	Mixed population of both low- and high-risk pregnancies N=159	RR 1.5 (95% CI 0.8 to 2.8)	Very low
1 study (Sharbaf 2014)	Prospective cohort	Very serious⁵	No serious inconsistency	No serious indirectness	Serious⁶	NICU admission	“Early labour”	Mixed population of both low- and high-risk pregnancies N=159	RR 2.3 (95% CI 1.2 to 4.2)	Very low
1 study (Sharbaf 2014)	Prospective cohort	Very serious⁵	No serious inconsistency	No serious indirectness	Serious⁶	NICU admission after excluding preterm birth	“Early labour”	Mixed population of both low- and high-risk pregnancies N=159	RR 2.0 (95% CI 1.0 to 4.1)	Very low
1 study (Sharbaf 2014)	Prospective cohort	Very serious⁵	No serious inconsistency	No serious indirectness	Very serious⁷	Umbilical artery pH ≤7.2	“Early labour”	Low-risk population only N=82	RR 1.05 (95% CI 0.4 to 3.0)	Very low
1 study (Sharbaf 2014)	Prospective cohort	Very serious⁵	No serious inconsistency	No serious indirectness	Very serious⁷	NICU admission	“Early labour”	Low-risk population only N=82	RR 1.0 (95% CI 0.3 to 3.4)	Very low
1 study (Sharbaf 2014)	Prospective cohort	Very serious⁵	No serious inconsistency	No serious indirectness	Very serious⁷	NICU admission after excluding preterm birth	“Early labour”	Low-risk population only N=82	RR 0.7 (95% CI 0.2 to 3.1)	Very low

BD base deficit; CI confidence interval; FHR fetal heart rate; NICHD National Institute of Child Health and Human Development; NR not reported; OR odds ratio; RR risk ratio; SD standard deviation

a

Criteria for classification of FHR as predictive, suspect, and non-predictive of fetal asphyxia on the basis of a 10 minute cycle of FHR tracing

Predictive: Absent baseline variability (repetitive cycle) ≥ 1 and presence of late or prolong decelerations ≥ 2 or presence of minimal baseline variability (repetitive cycle) ≥ 2 and presence of late or prolonged decelerations ≥ 2
Suspect: Presence of minimal baseline variability (repetitive cycle ≥ 2) and late or prolong decelerations (repetitive cycle ≥ 0/1) or presence of minimal baseline variability (repetitive cycle ≥ 0/1) and late or prolonged decelerations ≥ 2 repetitive cycle
Non-predictive: Minimal baseline variability (repetitive cycle 1) and no late or prolonged decelerations

b

No definition for “Normal” FHR tracing reported. Abnormal FHR defined as:

Mild bradycardia (FHR 90 – 119 bpm)
Moderate bradycardia (FHR 60 – 89 bpm)
Marked or severe bradycardia (FHR below 60 bpm)
Tachycardia (FHR ≥ 160 bpm)

1

Unclear if the assessors were blinded to outcomes

2

Small numbers of participants in severe category

3

No definition for FHR patterns reported

4

Women’s demographic characteristics not reported

5

No adjustments for potential confounders, no description of statistical methods. Only 20–40 minutes of CTG tracing interpreted in ‘early labour’

6

95% CI crosses 1.25

7

95% CI crosses 0.75 and 1.25

From: Appendix I, GRADE tables

Addendum to intrapartum care: care for healthy women and babies.

Clinical Guideline, No. 190.1.

National Guideline Alliance (UK).

London: National Institute for Health and Care Excellence (NICE); 2017 Feb.

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