The objective of the study was to perform serial magnetomyographic examinations in order to detect changes in synchrony characteristics of myometrial electrophysiological activity as women approach labor. Of the total of 56 patients recruited, the results of 149 examinations from 29 patients were included in the analysis. The global synchrony across each sensor spread over the abdomen was computed and quantified as synchronization index. The mean and the median value of the global synchrony were computed and correlated with time to active labor from the last recording. Overall, synchrony increased as the patient approached active labor (P = .035). Furthermore, mean synchronization index increased twice as fast in the nonnulliparous group compared to the nulliparous group (P = .039). The changes in synchrony of uterine electrophysiological activity near term could aid in prediction of labor.
MorrisonJMartinJMartinRGookinKWiserW. Prevention of preterm birth by ambulatory assessment of uterine activity: a randomized study. Am J Obstet Gynecol. 1987;156(3):536–537.
3.
McCormickMC. The contribution of low birth weight to infant mortality and childhood morbidity. N Engl J Med. 1985;312(2):82–90.
4.
ReichmannJP. Home uterine activity monitoring: the role of medical evidence. Obstet Gynecol. 2008;112(2 pt 1):325–327.
5.
DevedeuxDMarqueCMansourSGermainGDucheneJ. Uterine electromyography: a critical review. Am J Obstet Gynecol. 1993;169(6):1636–1653.
6.
KaoCY. Long-term observations of spontaneous electrical activity of the uterine smooth muscle. Am J Physiol. 1959;196(2):343–350.
7.
MarshallJM. Regulation of activity in uterine smooth muscle. Physiol Rev Suppl. 1962;5:213–227.
8.
YoungRC. Myocytes, myometrium, and uterine contractions. Ann N Y Acad Sci. 2007;1101:72–84.
9.
LammersWJ. The electrical activities of the uterus during pregnancy. Reprod Sci. 2013;20(2):182–189.
10.
MillerSMGarfieldREDanielEE. Improved propagation in myometrium associated with gap junctions during parturition. Am J Physiol. 1989;256(1 pt 1):C130–C141.
11.
CsapoAITakedaH. Electrical activity of the parturient human uterus. Nature. 1963;200:680–682.
12.
CsapoAITakedaH. Effect of progesterone on the electric activity and intrauterine pressure of pregnant and parturient rabbits. Am J Obstet Gynecol. 1965;91:221–231.
13.
VerhoeffAGarfieldRERamondtJWallenburgHC. Electrical and mechanical uterine activity and gap junctions in peripartal sheep. Am J Obstet Gynecol. 1985;153(4):447–454.
14.
WolfsGMvan LeeuwenM. Electromyographic observations on the human uterus during labour. Acta Obstet Gynecol Scand Suppl. 1979;90:1–61.
15.
EswaranHPreisslHWilsonJDMurphyPLoweryCL. First magnetomyographic recordings of the uterine activity with spatial–temporal resolution using a 151 channel sensor array. Am J Obstet Gynecol. 2002;187(1):145–151.
16.
EswaranHPreisslHWilsonJDMurphyPLoweryCL. Prediction of labor it term and preterm pregnancies using non-invasive magnetomyographic recordings of uterine contractions. Am J Obstet Gynecol. 2004;190(6):1598–1602.
17.
EswaranHGovindanRBFurdeaAMurphyPLoweryCLPreisslH. Extraction, quantification and characterization of uterine magnetomyographic activity—a proof of concept case study. Eur J Obstet Gynecol Rep Biol. 2009;144(suppl 1):S96–S100.
18.
FurdeaAEswaranHWilsonJDPreisslHLoweryCLGovindanRB. Magnetomyographic recording and identification of uterine contractions using Hilbert-wavelet transforms. Physiol Meas. 2009;30(10):1051–1060.
19.
SwearingenCJTilleyBCAdamsRJ. Application of beta regression to analyze ischemic stroke volume in NINDS rt-PA clinical trials. Neuroepidemiology. 2011;37(2):73–82.
20.
TaggartMJBlanksAKharcheSHoldenAWangBZhangH. Towards understanding the myometrial physiome: approaches for the construction of a virtual physiological uterus. BMC Pregnancy Childbirth. 2007;7(suppl 1):S3.
21.
RamonCPreisslHWilsonJDMurphyPLoweryCLEswaranH. Synchronization analysis of uterine magnetic activity during contractions. BioMed Eng Online. 2005;4:55–59.
22.
GarfieldREBlennerhassettMGMillerSM. Control of myometrial contractility: role and regulation of gap junctions. Oxf Rev Reprod Biol. 1988;10:436–490.
23.
GarfieldREManerWLMacKayLBSchlembachDSaadeGR. Comparing uterine electromyography activity of antepartum patients versus term labor patients. Am J Obstet Gynecol. 2005;193(1):23–29.
24.
GarfieldREManerWL. Physiology and electrical activity of uterine contractions. Semin Cell Dev Biol. 2007;18(3):289–295.
25.
LucovnikMManerWLChamblissLR. Noninvasive uterine electromyography for prediction of preterm delivery. Am J Obstet Gynecol. 2011;204(3):228.e1–e10.
26.
JiangWLiGLinL. Uterine electromyogram topography to represent synchronization of uterine contractions. Int J Gynaecol Obstet. 2007;97(2):120–124.
27.
NealJLLoweNKAhijevychKLPatrickTECabbageLACorwinEJ. “Active labor” duration and dilation rates among low-risk, nulliparous women with spontaneous labor onset: a systematic review. J Midwifery Womens Health. 2010;55(4):308–318.
28.
HilliardAMChauhanSPZhaoYRankinsNC. Effect of obesity on length of labor in nulliparous women. Am J Perinatol. 2012;29(2):127–132.
29.
DenisonFCPriceJGrahamCWildSListonWA. Maternal obesity, length of gestation, risk of postdates pregnancy and spontaneous onset of labour at term. BJOG. 2008;115(6):720–725.
30.
MargriplesUKershawTSRisingSSWestdahlCIckovicsJR. The effects of obesity and weight gain in young women on obstetric outcomes. Am J Perinatol. 2009;26(5):365–371.
31.
BeyerDAAmariFLuddersDWDiedrichKWeichertJ. Obesity decreases the chance to deliver spontaneously. Arch Gynecol Obstet. 2011;283(5):981–988.
