On February 15th, the Cochrane Library published a new review comparing cardiotocography (CTG) to intermittent auscultation of fetal heart rate on admission to the labor ward for assessment of fetal well-being (1). The results of the review support current recommendations from healthcare providers worldwide. How well are these recommendations being following in hospitals today? Read on...

What is an admission cardiotocograph?

When it was introduced to the maternity ward, the electronic fetal monitoring (EFM) machine was seen as a superior alternative to intermittent auscultation for the assessment of fetal well-being. Today, many women entering the labor ward with signs of labor are monitored for about 20 minutes using an EFM machine. This 20-minute screening test, which measures fetal heart rate and uterine activity, is called an admission cardiotocograph (CTG) or 'admission strip'. The test is performed to identify fetuses with a high risk of adverse perinatal outcomes.

Results from Devane et al.

Four studies, including 11,338 low-risk women, were reviewed (1). Admission CTG, when compared to intermittent auscultation, increased the risk of cesarean section (RR 1.20, 95% CI of 1.00 to 1.44). Women allocated to admission CTG also had an increased risk of continuous EFM during labor (RR 1.30, 95% CI 1.14 to 1.48) and increased risk of fetal blood sampling (RR 1.28, 95% CI 1.13-1.45). Admission CTG did not have an effect on amniotomy, oxytocin augmentation, epidural, instrumental vaginal birth, APGAR score less than 7 at 5 minutes, hypoxic ischaemic encephalopathy, admission to NICU, length of stay in NICU, neonatal seizures, and fetal multi-organ compromise within the first 24 hours after birth. From these results, the reviewers concluded that the use of the admission CTG for low-risk women had no benefit and increased risk of cesarean birth and continuous EFM.

How this Cochrane review compares to current knowledge

The last systematic review comparing admission CTG to intermittent auscultation was published in 2007 in the International Journal of Nursing Studies (2). This review by Gourounti and Sandall included three of the four studies reviewed by Devane (3-5). Gourounti and Sandall concluded that admission CTG resulted in increased risk for cesarean birth (RR 1.2 95% CI 1.00-1.41) and instrumental vaginal birth (RR 1.1 95% CI 1.00 - 1.18). With the addition of Mitchell's 2008 randomized controlled trial, Devane's 2012 review did not measure a significant difference in rates of instrumental vaginal birth (6).

Current recommendations for admission cardiotocography in low-risk women

Admission CTG is currently not recommended for low-risk women at term in labor by several organizations, including the Society of Obstetricians and Gynecologists of Canada and the Royal College of Obstetricians and Gynecologists (7-8). The American College of Obstetricians and Gynecologists does not explicitly discuss admission CTG in their most recent clinical practice guidelines of intrapartum fetal heart rate monitoring (9). Instead, they state that either EFM or intermittent auscultation may be used in labour for healthy women with no complications.

Recommendations from Lamaze

Admission fetal heart monitoring is addressed in Lamaze Healthy Birth Practice #4: Avoid Interventions That Are Not Medically Necessary:

'Like continuous EFM, admission EFM became widespread before any studies were conducted to show clinical effectiveness. Also, like continuous EFM, admission EFM does not produce anticipated benefits and, instead, increases harm (increased operative deliveries). (10)'

Lamaze recommends that all expectant women talk with their health-care providers about using auscultation or EFM. There are specific medical complications and interventions where EFM is necessary. Otherwise, it is safer and healthier to have intermittent auscultation.

The current reality of admission CTG

Despite the fact that admission CTG has no benefits when compared to intermittent auscultation, the majority of hospitals require all laboring women to undergo an admission CTG upon arrival. The most recent numbers available show admission CTG was used by approximately 79% of maternity units in the UK, by 96% of units in Ireland, by 76% of Canadian hospitals and 100% of labour units in Sweden (1).

Now to you, the reader. Where do we go from here? Your thoughts, as always, are very welcome!

References

1. Devane D, Lalor JG, Daly S, McGuire W, Smith V. Cardiotocography versus intermittent auscultation of fetal heart on admission to labour ward for assessment of fetal wellbeing. Cochrane Database of Systematic Reviews 2012, Issue 2. Art. No.: CD005122. DOI: 10.1002/14651858.CD005122.pub4.

2. Gourounti, K., & Sandall, J. (2007). Admission cardiotocography versus intermittent auscultation of fetal heart rate: Effects on neonatal Apgar score, on the rate of caesarean sections and on the rate of instrumental delivery - A systematic review. International Journal of Nursing Studies, 44(6), 1029-1035.

3. Cheyne H, Dunlop A, Shields N, Mathers AM. A randomised controlled trial of admission electronic fetal monitoring in normal labour. Midwifery2003;19:221-9.

4. Impey L, Reynolds M, MacQuillan K, Gates S, Murphy J, Sheil O. Admission cardiotocography: a randomised controlled trial. Lancet2003;361(9356):465-70.

5. Mires G, Williams F, Howie P. Randomised controlled trial of cardiotocography versus doppler auscultation of fetal heart at admission in labour in low risk obstetric population. BMJ2001;322:1457-60.

6. Mitchell K. The effect of the labour electronic fetal monitoring admission test on operative delivery in low-risk women: a randomised controlled trial. Evidence Based Midwifery2008;6(1):18-26.

7. Liston R, Sawchuck D, Young D. Fetal health surveillance: antepartum and intrapartum consensus guideline. Journal of Obstetrics & Gynaecology Canada: JOGC2007;29(9 Suppl 4):S3-S56.

8. Royal College of Obstetricians and Gynaecologists. The use of electronic fetal monitoring: the use and interpretation of cardiotocography in intrapartum fetal surveillance. Evidence-based Clinical Guideline Number 8. London: Royal College of Obstetricians and Gynaecologists, 2001.

9. The American College of Obstetricians and Gynecologists. Practice Bulletin Number 106. Obstetrics and Gynecology. 2009;114:192-202.

10. Lothian, J. Healthy Birth Practices from Lamaze International #4: Avoid interventions that are not medically necessary. 2009.

Published: March 13, 2012

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