Vol 92, No 3 (2021)
Research paper
Published online: 2021-03-17

open access

Page views 717
Article views/downloads 607
Get Citation

Connect on Social Media

Connect on Social Media

The assessment of selected parameters of bioelectric and mechanical activity of the uterus during pharmacologic treatment of threatening preterm delivery

Marek Tomialowicz1, Mariusz Zimmer1, Tomasz Fuchs1, Adam Matonia2
Pubmed: 33757150
Ginekol Pol 2021;92(3):183-187.


Objectives: To analyze and compare the bioelectric and mechanical activity of the uterus in pregnant women with threatening
preterm delivery treated with tocolysis. Additionally, auxiliary parameters of the bioelectric signal, as registered by
electrohysterography and characteristic only for this method, were measured and analyzed.
Material and methods: Forty-five women with pregnancies from 24 to 36 weeks of gestation with typical clinical symptoms
of threatening preterm delivery were given tocolytic therapy. Registration and analysis of bioelectric activity with
electrohysterography was performed simultaneously with registration and analysis of mechanical activity with tocography.
Results: After administration of tocolytic treatment, the presence of bioelectric activity was accompanied by the lack of or
minimal occurrence of mechanical activity. All parameters of contraction recorded by electrohysterography had significantly
greater values than those recorded by tocography.
Conclusions: Measurement of bioelectric activity is more sensitive than measurement of mechanical activity of the
uterus. Elevated bioelectric activity of the uterine muscle was observed despite the use of tocolysis, a lack of symptoms
of threatening preterm delivery, as well as a lack of contraction in tocography. The presence of bioelectric activity may
precede the occurrence of mechanical activity of the uterus, but further research is required on larger groups of patients.

Article available in PDF format

View PDF Download PDF file


  1. Beck S, Wojdyla D, Say L, et al. The worldwide incidence of preterm birth: a systematic review of maternal mortality and morbidity. Bull World Health Organ. 2010; 88(1): 31–38.
  2. Yochum M, Laforêt J, Marque C. An electro-mechanical multiscale model of uterine pregnancy contraction. Comput Biol Med. 2016; 77: 182–194.
  3. Buhimschi CS, Saade GR, Buhimschi IA, et al. Electrical activity of the human uterus during pregnancy as recorded from the abdominal surface. Obstet Gynecol. 1997; 90(1): 102–111.
  4. Schwalm H, Dubrauszky V. The structure of the musculature of the human uterus--muscles and connective tissue. Am J Obstet Gynecol. 1966; 94(3): 391–404.
  5. Garfield RE, Blennerhassett MG, Miller SM. Control of myometrial contractility: role and regulation of gap junctions. Oxf Rev Reprod Biol. 1988; 10: 436–490.
  6. Steer CM, Hertsch GJ. Electrical activity of the human uterus in labor; the electrohysterograph. Am J Obstet Gynecol. 1950; 59(1): 25–40.
  7. Wolfs G, van Leeuwen M, Rottinghuis H, et al. An electromyographic study of the human uterus during labor. Obstet Gynecol. 1971; 37(2): 241–246.
  8. Jacod BC, Graatsma EM, Van Hagen E, et al. A validation of electrohysterography for uterine activity monitoring during labour. J Matern Fetal Neonatal Med. 2010; 23(1): 17–22.
  9. Fele-Zorz G, Kavsek G, Novak-Antolic Z, et al. A comparison of various linear and non-linear signal processing techniques to separate uterine EMG records of term and pre-term delivery groups. Med Biol Eng Comput. 2008; 46(9): 911–922.
  10. Buhimschi C, Garfield RE. Uterine contractility as assessed by abdominal surface recording of electromyographic activity in rats during pregnancy. Am J Obstet Gynecol. 1996; 174(2): 744–753.
  11. Hubinont C, Debieve F. Prevention of preterm labour: 2011 update on tocolysis. J Pregnancy. 2011; 2011: 941057.
  12. Zietek J, Sikora J, Horoba K, et al. Mechanical and electrical uterine activity. Part II. Contractions parameters. Ginekol Pol. 2008; 79(11): 798–804.
  13. Duchene J, Devedeux D, Mansour S, et al. Analyzing uterine EMG: tracking instantaneous burst frequency. IEEE Engineering in Medicine and Biology Magazine. 1995; 14(2): 125–132.
  14. Gondry J, Marque C, Duchene J, et al. Electrohysterography during pregnancy: preliminary report. Biomed Instrum Technol. 1993; 27(4): 318–324.
  15. Sananès N, Langer B, Gaudineau A, et al. Prediction of spontaneous preterm delivery in singleton pregnancies: where are we and where are we going? A review of literature. J Obstet Gynaecol. 2014; 34(6): 457–461.
  16. Zietek J, Sikora J, Horoba K, et al. Mechanical and electrical uterine activity. Part I. Contractions monitoring. Ginekol Pol. 2008; 79(11): 791–797.
  17. Euliano TY, Nguyen MT, Darmanjian S, et al. Monitoring uterine activity during labor: a comparison of 3 methods. Am J Obstet Gynecol. 2013; 208(1): 66.e1–66.e6.
  18. Hadar E, Biron-Shental T, Gavish Oz, et al. A comparison between electrical uterine monitor, tocodynamometer and intra uterine pressure catheter for uterine activity in labor. J Matern Fetal Neonatal Med. 2015; 28(12): 1367–1374.
  19. Kawarabayashi T, Kishikawa T, Sugimori H. Characteristics of action potentials and contractions evoked by electrical-field stimulation of pregnant human myometrium. Gynecol Obstet Invest. 1988; 25(2): 73–79.
  20. Rabotti C, Mischi M. Propagation of electrical activity in uterine muscle during pregnancy: a review. Acta Physiol (Oxf). 2015; 213(2): 406–416.
  21. Aviram A, Hiersch L, Ashwal E, et al. The association between myometrial electrical activity and time to delivery in threatened preterm labor. J Matern Fetal Neonatal Med. 2016; 29(18): 2897–2903.
  22. Kandil M, Emarh M, Ellakwa H. Abdominal electromyography in laboring and non-laboring pregnant women at term and its clinical implications. Arch Gynecol Obstet. 2013; 288(2): 293–297.
  23. Maner WL, Garfield RE, Maul H, et al. Predicting term and preterm delivery with transabdominal uterine electromyography. Obstet Gynecol. 2003; 101(6): 1254–1260.
  24. Garfield RE, Maner WL, MacKay LB, et al. Comparing uterine electromyography activity of antepartum patients versus term labor patients. Am J Obstet Gynecol. 2005; 193(1): 23–29.
  25. Zietek J, Sikora J, Horoba K, et al. Prognostic value of chosen parameters of mechanical and bioelectrical uterine activity in prediction of threatening preterm labour. Ginekol Pol. 2009; 80(3): 193–200.
  26. Kandil MA, Abdel-Sattar MM, Abdel-Salam SM, et al. Abdominal electromyography may predict the response to tocolysis in preterm labor. Eur J Obstet Gynecol Reprod Biol. 2012; 160(1): 18–21.
  27. Vinken MP, Rabotti C, Mischi M, et al. Accuracy of frequency-related parameters of the electrohysterogram for predicting preterm delivery: a review of the literature. Obstet Gynecol Surv. 2009; 64(8): 529–541.