Uterine Activity Monitoring during Labour – A Multi-Centre, Blinded Two-Way Trial of External Tocodynamometry against Electrohysterography

Abstract

Purpose:

The aim of this study was to determine the quality of intrapartum uterine activity (UA) monitoring in daily practice during the first and second stages of labour. The total duration of inadequate UA monitoring is quantified in relation to the technique applied, namely, external tocodynamometry (TOCO) or electrohysterography (EHG).

Material and Methods:

144 UA recordings, collected from 1^st September 2008 until 15^th October 2009 from deliveries at the Marien-Hospital Witten, Germany, were analysed by obstetricians based at different centres. The included recordings were from singleton and simultaneously with external TOCO and EHG monitored pregnancies. External TOCO and EHG UA recordings were blinded.

Results:

The percentages of “adequate” UA recordings in the first and second stages of labour were much higher for the external EHG than the external TOCO mode (p<0.001). All doctors evaluated the UA assessment as “easier” (p <0.001) using the EHG compared with TOCO.

Conclusion:

Intrapartum UA monitoring in ­daily practice via the EHG mode provides a more re­cognisable UA trace than the TOCO.

Zusammenfassung

Fragestellung:

Ziel dieser Studie ist die Qua­litätsbeurteilung der Wehentätigkeitsaufzeichnung (UA) in der ersten und zweiten Geburts­phase. Die adäquate Aufzeichnungsperiode und Qualität wurde nach Aufzeichnungstechnik (Tokogramm (TOCO) vs. Elektrohystogramm (EHG)) evaluiert.

Material und Methodik:

144 UA-Aufzeichnungen, bei denen gleichzeitig TOCO und EHG abgeleitet wurden, wurden durch Gynäkologen/in bei unterschiedlichen Zentren beurteilt. Die Auf­zeichnungen wurden verblindet ausgewertet.

Ergebnisse:

Adäquate UA-Aufzeichnungen waren häufiger bei dem EHG im Vergleich zum TOCO (während der ersten und zweiten Geburts­phase; p<0,001). Alle Ärzte beurteilten EHG-Qualität Wehentätigkeit als besser (p<0,001).

Schlussfolgerung:

Unter der Geburt zeigt das EHG mehr adäquate UA-Aufzeichnung und bessere Beurteilbarkeit als der „Goldstandard“ TOCO.

Key words

electrohysterography - uterine activity monitoring - tocography - quality

Schlüsselwörter

Elektrohysterogram - Wehentätigkeit - Tokogram - Qualität

• References

• 1 Thacker SB, Stroup D, Chang M. Continuous electronic heart rate monitoring for fetal assessment during labour (Review). The Cochrane Database of Systemic Reviews 2001; Issue 2. Art. No.: CD000063 CD000063
• 2 Vanner T, Gardosi J. Intrapartum assessment of uterine activity. Baillieres Clin Obstet Gynaecol 1996; 10: 243-257
• 3 Bakker PC, Zikkenheimer M, van Geijn HP. The quality of intrapartum uterine activity monitoring. J Perinat Med 2008; 36: 197-201
• 4 Miles AM, Monga M, Richeson KS. Correlation of external and internal monitoring of uterine activity in a cohort of term patients. Am J Perinatol 2001; 18: 137-140
• 5 ACOG practice bulletin . Intrapartum fetal heart rate monitoring. Obstet Gynecol 2005; 106: 1453-1461
• 6 FIGO news . Intrapartum surveillance: recommendations on current practice and overview of new developments. Int J Gynaecol Obstet 1995; 49: 213-221
• 7 The use of cardiotocography in intrapartum fetal surveillance. Evidencebased Clinical Guideline Number 8. Clinical Effectiveness Support Unit. RCOG Press; London: 2001
• 8 Williams B, Arulkumaran S. Cardiotocography and medicolegal issues. Best Pract Res Clin Obstet Gynaecol 2004; 18: 457-466
• 9 Bakker PC, van Geijn HP. Uterine activity: implications for the condition of the fetus. J Perinat Med 2008; 36: 30-37
• 10 Steer CM, Hertsch GJ. Electrical activity of the human uterus in labour; the electrohysterograph. Am J Obstet Gynecol 1950; 59: 25-40
• 11 Wolfs GM, van Leeuwen M. Electromyographic observations on the human uterus during labour. Acta Obstet Gynecol Scand Suppl 1979; 90: 1-61
• 12 Devedeux D, Marque C, Mansour S et al. Uterine electromyography: a critical review. Am J Obstet Gynecol 1993; 169: 1636-1653
• 13 Maner WL, Garfield RE. Identification of human term and preterm labour using artificial neural networks on uterine electromyography data. Ann Biomed Eng 2007; 35: 465-473
• 14 Maul H, Maner WL, Olson G et al. Non-invasive transabdominal uterine electromyography correlates with the strengt hof intrauterine pressure and is predicitive of labour and delivery. J Matern Fetal Neonatal Med 2004; 15: 297-301
• 15 Garfield RE, Maner WL, Mac Kay LB et al. Comparing uterine electromyo­graphy activity of antepartum patients versus term labour patients. Am J Obstet Gynecol 2005; 193: 23-29
• 16 Garfield RE, Maner WL. Physiology and electrical activity of uterine contractions. Semin Cell Dev Biol 2007; 18: 289-295
• 17 Maner WL, Garfield RE, Maul H et al. Predicting term and preterm delivery with transabdominal uterine electromyography. Obstet Gynecol 2003; 101: 1254-1260
• 18 Garfield RE, Maner WL, Maul H et al. Use of uterine EMG and cervical LIF in monitoring pregnant patients. BJOG 2005; 112 (Suppl. 01) 103-108
• 19 Jacod BC, Graatsma EM, van Hagen E et al. A validation of electrohysterography for uterine activity monitoring during labour. J Matern Fetal Neonatal Med 2009; Aug 11: 1-6 [Epub ahead of print]
• 20 Maner WL, MacKay LB, Saade GR et al. Characterisation of abdominally acquired uterine electrical signals in humans, using a non-linear analytic method. Med Biol Eng Comput 2006; 44: 117-123
• 21 Rabotti C, Mischi M, van Laar JO et al. Estimation of internal uterine pressure by joint amplitude and frequency analysis of electrohysterographic signals. Physiol Meas 2008; 29: 829-841
• 22 Euliano T, Skowronski M, Marossero D et al. Prediction of intrau­terine pressure waveform from trans-abdominal electrohysterography. J Matern Fetal Neonatal Med 2006; 19: 811-816
• 23 Skowronski MD, Harris JG, Marossero DE et al. Prediction of intrauterine pressure from electro-hysterography using optimal linear filtering. IEEE Trans Biomed Eng 2006; 53: 1983-1989
• 24 Euliano TY, Nguyen MT, Marossero D et al. Monitoring contractions in obese parturients: electrohysterography compared with traditional monitoring. Obstet Gynecol 2007; 109: 1136-1140
• 25 Jezewski J, horoba K, Matonia A et al. Quantitative analysis of contraction patterns in electrical activity signal of pregnant uterus as an alternative to mechanical approach. Physiol Meas 2005; 26: 753-767
• 26 Freeman RK, Garite TJ, Mp Nageotte. eds. Uterine contraction monitoring. In: Fetal heart rate monitoring. 3^rd ed. Philadelphia, United States: Lippencott Williams & Wilkens; 2003: 54-62
• 27 Chia YT, Arulkumaran S, Soon SB et al. Induction of labour: does internal tocography result in beter obstetric outcome than external tocography. Aust NZ J Obstet Gynaecol 1993; 33: 159-161
• 28 Chua S, Kurup A, Arulkumaran S et al. Augmentation of labour: does internal tocography result in better obstetric outcome than external monitoring?. Obstet Gynecol 1990; 76: 164-167
• 29 Euliano TY, Nguyen MT, Marossero D et al. Monitoring contractions in obese parturients: electrhysterography compared with traditional monitoring. Obstet Gynecol 2007; 109: 1136-1140
• 30 Vanner T, Gardosi J. Intrapartum assessment of uterine activity. Baillieres Clin Obstet Gynaecol 1996; 10: 243-257