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Uterine activity plays a crucial role in labor, especially when utero-tonic materials are administered. We aimed to determine the electrical responsiveness of the uterine musculature to labor augmentation with oxytocin using electrical uterine myography (EUM) technology, and to assess whether the kinetics of the EUM device may serve as a predictor for successful vaginal delivery. EUM prospectively measured electrical uterine activity in women with singleton gestations at term (≥ 37 + 0 weeks) undergoing labor augmentation by oxytocin administration. The results were reported as the EUM index, which represented the mean electrical activity in 10-min intervals and measured in units of microwatt per second (mW/s). Measurements were performed at least 30 min before oxytocin initiation and until at least four contractions per 10 min were recorded by standard tocodynamometry. The delta EUM index was defined as the difference between the mean EUM index before and after the initiation of oxytocin. The mean EUM index increased significantly during oxytocin augmentation in all the parturients (P

Antenatal corticosteroids before preterm births are considered to be most effective 48 h after and up to 1 week after the first dose. We aim to evaluate: (1) our practice of administration of antenatal corticosteroids in Singapore; (2) admission characteristics of women for discriminatory factors of spontaneous preterm delivery within 1 week. This is a retrospective study in a tertiary obstetrics unit in Singapore. 3044 women who delivered live births (at term or preterm) from 1st November 2014 to 31st January 2015, who were at risk of spontaneous or induced preterm delivery, were included. Data related to the time of and indications for antenatal corticosteroids administration, characteristics assessed at the time of presentation, and time of delivery were collected and analysed. 85.9% of women who delivered at gestational age ≤ 34+6 received at least one dose. 22.1% had delivered within the window of efficacy. Gestational age > 32 weeks at presentation, uterine activity on tocography and cervical dilation with effacement were associated with preterm delivery within 1 week of presentation. Overall, our antenatal corticosteroids administration rate is comparable to that attained by centres in other developed countries. It is difficult but important to discriminate women who will benefit from this timely intervention.

PURPOSE: To compare diagnostic accuracy of sonographic cervical length (CL) measurement and uterine electric activity assessed by electromyography (EMG) in second trimester regarding prediction of preterm delivery (PTD). ----- METHODS: Prospective study of 308 low-risk women. Shortened CL was defined as ≤25 mm (≤5th centile), while raised EMG activity was defined as the presence of ≥20 action potentials in 20 min of assessment (≥95th centile). Outcome measures were diagnostic accuracy of both tests alone or in combination for prediction of PTD and early PTD (≤34 weeks). ----- RESULTS: The incidence of PTD was 23/308 (7.4%) while the incidence of early PTD was 9/308 (2.9%). Shortened CL and raised EMG activity were significantly related to PTD [prevalence-weighted likelihood ratio (pw-LR) 1.9, 95% CI 1.0-3.5 vs. 9.5, 95% CI 2.5-35.7], but not to early PTD (pw-LR 0.4, 95% CI 0.2-0.8 vs. 0.6, 95% CI 0.3-1.7). Significant predictive value for early PTD was found only if both tests were combined (pw-LR 4, 95% CI 1.3-14.3). ----- CONCLUSION: Shortened CL and raised EMG activity in second trimester have significant diagnostic accuracy regarding prediction of PTD in a low-risk population. However, in order to be useful as a predictor for early PTD both tests must be positive.

In a prospective study, 140 patients had an oxytocin challenge test with either a continuous or a pulsed infusion (one minute of infusion in every five minutes). Both infusion regimens had similar success rates in terms of uterine contractions (97.1 vs 98.6%). The potency ratio (pulsed versus continuous infusion) was significant at 2.7 (1.27 to 5.2), which means that more uterine activity was induced with each mU of oxytocin with pulsatile than with continuous administration. The total amount of oxytocin required to obtain three good contractions in 10 minutes was about 40% less with pulsed administration than with continuous infusion, but the test took 40 minutes longer with the pulsed than with the continuous infusion (P < 0.01).

Purpose: Timely diagnosing a uterine rupture is challenging. Based on the pathophysiology of complete uterine wall separation, changes in uterine activity are expected. The primary objective is to identify tocogram characteristics associated with uterine rupture during trial of labor after cesarean section. The secondary objective is to compare the external tocodynamometer with intrauterine pressure catheters. Methods: MEDLINE, EMBASE, and the Cochrane library were systematically searched for eligible records. Moreover, clinical guidelines were screened. Studies analyzing tocogram characteristics of uterine rupture during trial of labor after cesarean section were appraised and included by two independent reviewers. Due to heterogeneity, a meta-analysis was only feasible for uterine hyperstimulation. Results: Thirteen studies were included. Three tocogram characteristics were associated with uterine rupture. (1) Hyperstimulation was more frequently observed compared with controls during the delivery (38 versus 21 % and 58 versus 53 %), and in the last 2 h prior to birth (19 versus 4 %). Results of meta-analysis: OR 1.68 (95 % CI 0.97–2.89), p = 0.06. (2) Decrease of uterine activity was observed in 14–40 % and (3) an increasing baseline in 10–20 %. Five studies documented no changes in uterine activity or Montevideo units. A direct comparison between external tocodynamometer and intrauterine pressure catheters was not feasible. Conclusions: Uterine rupture can be preceded or accompanied by several types of changes in uterine contractility, including hyperstimulation, reduced number of contractions, and increased or reduced baseline of the uterine tonus. While no typical pattern has been repeatedly reported, close follow-up of uterine contractility is advised and hyperstimulation should be prevented.