Soon after its introduction, electronic fetal heart monitoring (EFM) had become established as best practice. But recent evidence has questioned both its role and its efficacy. When it is used the rates of both operative vaginal delivery and delivery by caesarean section are significantly increased, compared to labours where the midwife uses intermittent auscultation. Consequently there seems to be conclusive evidence that EFM increases the likelihood of intervention.
Which is not to suggest that electronic fetal monitoring isn't a useful or effective technique. The problem with EFM comes from its routine use in cases where it is not indicated, where it often replaces careful observation and auscultation by the midwife.
There are, of course, clinical situations when continuous EFM Is recommended (for instance, where a woman has an epidural, is having a syntocinon infusion or has a previous history of fetal distress). Even here, though, you should corroborate its readings with a Pinard Stethoscope. Ausculating the fetal heart in this way develops your expertise and heightens your clinical skills In detecting the fetal heart rate. This recognised best practice helps to prevent undue reliance on the technology.
The National Institute for Clinical Excellence (NICE) guidelines on EFM set out an evidence based approach. We strongly recommend that you familiarise yourself with them, and use them in your practice. If your organisation's policy on EFM currently differs from the NICE approach, you might want to question why this is the case (the situation can't change for the better unless someone challenges the status quo!)
Tips and tricks
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Don't use cardiotocography (CTG) for women with a low-risk pregnancy - there is no evidence that it is effective in this situation, and it is therefore not recommended.
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Use intermittent auscultation instead if a woman is healthy - and has had an uncomplicated pregnancy, as recommended in the NICE guidelines.
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Differentiate between the maternal and fetal heart rates - by taking her pulse at the same time as ausculating the fetal heart rate electronically. Record both. Use a Pinard stetescope to validate your findings.
Remember that when you use CTG or a doppler you are detecting the heart's actions (the RR interval of the ECG, i.e. it is machine mediated) but with a Pinard you are hearing the heart's sounds (blood flowing through the heart valves). In the active stages of labour, perform auscultation after a contraction for a minimum of 60 seconds (and at least every 15 minutes in the first stage and every 5 minutes in the second stage). Only switch to continuous EFM if there is evidence on auscultation of a baseline less than 110 or greater than 160 bpm, a change in rhythm, or if you pick up on any decelerations or if any intrapartum risk factors develop.
Further reading
Vintzileos AM, Nochimson DJ, Knuppel RA, Lake M, Schifrin BS (1995)
Intrapartum electronic fetal heart rate monitoring versus intermittent auscultation: a meta analysis Obstetrics & Gynaecology 85: 149-155
Thacker SB, Stroup DF.
Continous electronic fetal heart rate monitoring versus intermittent auscultation during labor. Cochrane Database Syst. Rev. (1999) (Issue no. 3)
Inherited Clinical Guideline C. The Use Of Electronic Fetal Monitoring: the use and interpretation of cardiotocography in intrapartum fetal surveillance (May 2001)
www.nice.org.uk/pdf/efmguidelinercog.pdf
Lavender T, Stephen A, Walkinshaw SA, Walton I (1999) A prospective study of women's views of factors contributing to a positive birth experience.
Midwifery 15: 40-46
