Uterine Contractions' Pattern in Active Phase of Labor as a Predictor of Failure to Progress

Abstract

Background:Failure to progress remains a key indication for cesarean section which caused by different factors including uterine contractions. If it is diagnosed in the primary phase of labor, a better prognosis can thus be made. The purpose of this study was to find a possible correlation between pattern of uterine contraction and progression of labor.Method:During this study, 120 women referred for delivery to an educational hospital’s maternity ward in the North of Iran in 2010 were included. Uterine contractions of mothers were recorded in dilatation of 4 to7 cm for an hour. In this way, F/R ratio which means the time that a contraction needs to return from its peak to baseline (Fall) divided to the time for a contraction to rise to its peak (Rise) was calculated. All of the participants were followed until delivery, vaginal delivery or caesarean section.Results:Mean and standard deviation of fall to raise ratio was 1.54 ± 0.26 in mothers with vaginal delivery versus 1.74 ± 0.21 for others underwent caesarean section (OR = 0.44, 95% CI: 0.005- 0.42, P < 0.001). Sensitivity, specificity, and predictive values (positive and negative) of mentioned ratio were 68.32%, 70.01%, 69.55%, and 68.91%, respectively.Conclusion:By considering acceptable predictive value of uterine contractions’ pattern in the active phase of labor, it could help to timely diagnosis of failure to progress and consequently suitable intervention which probably maintain better health of both mother and fetus.

An Integrated Review of Uterine Activity Monitoring for Evaluating Labor Dystocia

“…The sample included papers published between 2002 and 2016 that originated in 6 countries: the United States, Canada, Slovenia, Iran, South Africa, and the Netherlands. Sample sizes ranged from 28 to 36 women in 3 smaller feasibility studies, [10][11][12] 100 to 200 women in 7 observational case-control and cohort studies, [13][14][15][16][17][18][19] and 503 women in one randomized controlled trial. 20 Eight studies included only nulliparous women, [11][12][13][14][16][17][18][19] whereas 3 included women of any parity.…”

“…20 Eight studies included only nulliparous women, [11][12][13][14][16][17][18][19] whereas 3 included women of any parity. 10,15,20,21 Uterine activity was measured in a variety of ways including frequency of contractions, intrauterine pressure, electrical activity measured by uterine electromyography (EMG) power density spectrum, and measures of contraction organization such as the fall-to-rise ratio, SD of contraction frequency, spatiotemporal maps, and EMG sample entropy (Table 1). Although most researchers evaluated uterine activity at a single point in time, some used multiple time points or continuous data to identify patterns of change in uterine activity during labor.…”

“…The fall-to-rise ratio is a measure of contraction shape calculated as the time in seconds from the peak of the contraction to return to baseline divided by the time from contraction onset to the contraction peak (Figure 3). 16 The fall-to-rise ratio was reported in 4 studies, [15][16][17][18] 3 of which were conducted by the same research group in Iran. [15][16][17] Increased fall-to-rise ratio, which indicates a contraction that has a prolonged fall time compared with the rise time, was hypothesized by the researchers to indicate slow recovery of the uterine muscle following contraction.…”

“…16 The fall-to-rise ratio was reported in 4 studies, [15][16][17][18] 3 of which were conducted by the same research group in Iran. [15][16][17] Increased fall-to-rise ratio, which indicates a contraction that has a prolonged fall time compared with the rise time, was hypothesized by the researchers to indicate slow recovery of the uterine muscle following contraction. Althaus et al 18 conducted a case-control study evaluating fall-to-rise ratio in 100 nulliparous women with a term, singleton, vertex fetus who had cesarean birth for cephalopelvic disproportion or arrest of labor matched with 100 women who gave birth vaginally.…”

Sensitivitas, Spesifisitas dan Akurasi Pengukuran Kontraksi Uterus Kala I Fase Aktif Ibu Bersalin Menggunakan Tokodinamometer

“…Ibu bersalin pada fase aktif akan mengalami hipotonik atau hipertonik yang akan memengaruhi kemajuan persalinan serta memengaruhi kondisi janin. 6,7 Penggunaan kardiotokografi (KTG) berdasar atas beberapa penelitian yang menunjukkan bahwa KTG untuk mengidentifikasi kontraksi uterus pada persalinan mempunyai sensitivitas dan akurasi lebih rendah apabila dibanding dengan electrohysterography dan intrauterine pressure catheter (IUPC). 8,9 Kardiotokografi atau tokodinamometer kurang efektif dipakai pada ibu bersalin dengan obesitas (indeks massa tubuh atau IMT>35).…”