BACKGROUND
Tocodynamometry is a common, noninvasive tool used to measure contraction frequency;
however, its utility is often limited in patients with obesity. An intrauterine pressure
catheter provides a more accurate measurement of uterine contractions but requires
ruptured membranes, limiting its utility during early latent labor. Electrical uterine
myography has shown promise as a noninvasive contraction monitor with efficacy similar
to that of the intrauterine pressure catheter; however, its efficacy has not been
widely studied in the obese population.
OBJECTIVE
This study aimed to validate the accuracy of electrical uterine myography by comparing
it with tocodynamometry and intrauterine pressure catheters among laboring patients
with obesity.
STUDY DESIGN
This was a prospective observational study from February 2017 to April 2018 of patients
with obesity, aged 18 years or older, who were admitted to the labor unit with viable
singleton pregnancies and no contraindications for electromyography. Patients were
monitored simultaneously with electrical myography and tocodynamometry or intrauterine
catheter for more than 30 minutes. Two blinded obstetricians reviewed the tracings.
The outcomes of interest were continuous and interpretable tracing, number of contractions,
and timing and duration of contractions, interpreted as point estimates and associated
95% confidence intervals.
RESULTS
A total of 110 patients were enrolled (65 tocodynamometry, 55 intrauterine catheter).
Electrical myography was significantly more interpretable during a 30-minute tracing
(P=.001) and detected 39% more contractions than tocodynamometry (P<.0001; 95% confidence interval, 23%–57%), whereas there was no difference in the
interpretability of tracings or number of contractions between electrical myography
and an intrauterine catheter (P=.16; 95% confidence interval, –0.19 to 1.19). Patients who underwent simultaneous
monitoring preferred the electrical myography device over tocodynamometry.
CONCLUSION
Electrical uterine myography is superior to tocodynamometry in the detection of intrapartum
uterine contraction monitoring and comparable with internal contraction monitoring.
Key words
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References
- A comparison of surface acquired uterine electromyography and intrauterine pressure catheter to assess uterine activity.Am J Obstet Gynecol. 2012; 206: 412.e1-412.e5
- Non-invasive transabdominal uterine electromyography correlates with the strength of intrauterine pressure and is predictive of labor and delivery.J Matern Fetal Neonatal Med. 2004; 15: 297-301
- Monitoring uterine activity during labor: a comparison of 3 methods.Am J Obstet Gynecol. 2013; 208: 66.e1-66.e6
- Monitoring contractions in obese parturients: electrohysterography compared with traditional monitoring.Obstet Gynecol. 2007; 109: 1136-1140
- Prevalence of overweight and obesity in the United States, 1999-2004.JAMA. 2006; 295: 1549-1555
- Dystocia and augmentation of labor.Int J Gynaecol Obstet. 2004; 85: 315-324
- Dutch Society of Obstetrics and Gynaecology.Dutch Society of Obstetrics and Gynaecology, Induction of labor: guideline no. 5. Utrecht, the Netherlands2008
- Fetal health surveillance: antepartum and intrapartum consensus guideline.J Obstet Gynaecol Can. 2007; 29: S3-S56
- Fetal complications after placement of an intrauterine pressure catheter: a report of two cases and review of the literature.J Matern Fetal Neonatal Med. 2008; 21: 880-883
- Major complications associated with intrauterine pressure monitoring.Obstet Gynecol. 1982; 59: 389-391
- Anaphylactoid syndrome of pregnancy immediately after intrauterine pressure catheter placement.Am J Obstet Gynecol. 2008; 198: e8-e9
- Outcomes after internal versus external tocodynamometry for monitoring labor.N Engl J Med. 2010; 362: 306-313
- Induction of labour: does internal tocography result in better obstetric outcome than external tocography.Aust N Z J Obstet Gynecol. 1993; 33: 159-161
- Augmentation of labor: does internal tocography result in better obstetric outcome than external tocography?.Obstet Gynecol. 1990; 76: 164-167
- Noninvasive uterine electromyography for prediction of preterm delivery.Am J Obstet Gynecol. 2011; 204: 228.e1-228.e10
- Regulation of activity in uterine smooth muscle.Physiol Rev Suppl. 1962; 42: 213-227
- A study of the parturient uterus with the microelectrode technique.Endocrinology. 1967; 80: 748-753
- Uterine electromyography: a critical review.Am J Obstet Gynecol. 1993; 169: 1636-1653
- Electromyographic observations on the human uterus during labour.Acta Obstet Gynecol Scand Suppl. 1979; 90: 1-61
- Alteration of 24-hour rhythms in myometrial activity in the chronically catheterized pregnant rhesus monkey after a 6-hour shift in the light-dark cycle.Am J Obstet Gynecol. 1990; 163: 648-654
- A comparison between electrical uterine monitor, tocodynamometer and intra uterine pressure catheter for uterine activity in labor.J Matern Fetal Neonatal Med. 2015; 28: 1367-1374
- Models for longitudinal data: a generalized estimating equation approach.Biometrics. 1988; 44: 1049-1060
- Electrohysterography for uterine monitoring during term labour compared to external tocodynamometry and intra-uterine pressure catheter.Eur J Obstet Gynecol Reprod Biol. 2017; 215: 197-205
Article info
Publication history
Published online: April 11, 2021
Accepted:
April 6,
2021
Received in revised form:
March 29,
2021
Received:
February 14,
2021
Footnotes
This abstract was presented as a poster at the 39th annual pregnancy meeting of the Society for Maternal-Fetal Medicine, Las Vegas, NV, February 11–16, 2019.
The authors report no conflict of interest.
This study received no financial support.
This trial is registered with ClinicalTrials.gov under the unique identifier NCT02993354. Available at: https://clinicaltrials.gov/ct2/show/NCT02993354?term=NCT02993354&recrs=ab&cond=Fetal+Monitoring&cntry=US&state=US%3ANY&rank=1.
Cite this article as: Moni SS, Kirshenbaum R, Comfort L, et al. Noninvasive monitoring of uterine electrical activity among patients with obesity: a new external monitoring device. Am J Obstet Gynecol MFM 2021;XX:x.ex–x.ex.
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