Liat Salzer

Association of isolated polyhydramnios at or beyond 34 weeks of gestation and pregnancy outcome.

OBJECTIVE: To evaluate pregnancy outcome among women with isolated polyhydramnios at admission for labor at or beyond 34 weeks of gestation. METHODS: Retrospective cohort study at a tertiary medical center between 2007 and 2012. Isolated polyhydramnios was defined as amniotic fluid index (AFI) greater than 25 cm at admission in the absence of gestational or pregestational diabetes mellitus or fetal structural or chromosomal anomalies. Women with isolated polyhydramnios were compared with women with a normal AFI (5–25 cm). RESULTS: Overall, 31,376 women were eligible for analysis, of whom 215 (0.7%) had isolated polyhydramnios and 31,161 normal AFI. Women with isolated polyhydramnios had higher rates of labor induction (7.9% compared with 4.8%, P=.04) and cesarean delivery (12.1% compared with 5.1%, P<.001). They also had higher rates of placental abruption (0.9% compared with 0.2%, P=.02), abnormal or intermediate fetal heart rate (FHR) tracings (7.0% compared with 3.2%, P=.002), and prolonged first stage of delivery (6.0% compared with 1.4%, P<.001). Isolated polyhydramnios was also associated with higher rates of shoulder dystocia (1.9% compared with 0.3%, P<.001) and respiratory distress syndrome (0.5% compared with 0.03%, P=.001). On a multiple logistic regression model, isolated polyhydramnios was an independent risk factor for labor induction (adjusted odds ratio [OR] 1.7, 95% confidence interval [CI] 1.01–2.8), cesarean delivery (adjusted OR 2.6, 95% CI 1.7–4.0), prolonged first stage of delivery (adjusted OR 3.6, 95% CI 1.97–6.7), abnormal or intermediate FHR tracings (adjusted OR 2.6, 95% CI 1.6–4.5), placental abruption (adjusted OR 8.4, 95% CI 2.00–35.4), shoulder dystocia (adjusted OR 3.4, 95% CI 1.2–9.7), and respiratory distress syndrome (adjusted OR 38.9, 95% CI 4.6–332.6). Mild isolated polyhydramnios (AFI 25.1–30.0) was independently associated with cesarean delivery, prolonged first stage of delivery, placental abruption, abnormal or intermediate FHR tracings, and shoulder dystocia. CONCLUSION: Isolated polyhydramnios at admission for labor at or beyond 34 weeks of gestation is associated with adverse obstetric and neonatal outcomes. LEVEL OF EVIDENCE: II

Predictors of successful external cephalic version and assessment of success for vaginal delivery.

Abstract Objective: To identify predictors of successful external cephalic version (ECV) and to compare delivery outcome between women who had a successful ECV and women with spontaneous vertex presentation. Methods: A retrospective cohort study of all women who underwent ECV in a single tertiary medical center between 2007 and 2011. Delivery outcome was compared between women who underwent a trial of vaginal delivery following successful ECV with that of a control group in a 2:1 ratio. Multivariate analysis was used to identify predictors of successful ECV. Results: Overall 287 were eligible for the study group. Of these 130 (45.3%) had a successful ECV. Polyhydramnios was the strongest factor associated with successful ECV (OR = 3.1, 95%-CI 1.4–7.2), followed by transverse lie (versus breech presentation, OR= 2.6, 95%-CI 1.2–6.7) and a posterior placenta (OR= 1.7, 95%-CI 1.1–3.9), while nulliparity was associated with a lower likelihood of successful ECV (OR= 0.4, 95%-CI 0.2–0.6). Women who had a successful ECV and underwent a trial of labor were more likely to deliver by operative vaginal delivery (OVD) (OR= 1.8, 95%-CI 1.2–3.6), mainly due to a higher rate of prolonged 2nd, but were not at an increased risk for CS (OR= 0.9, 95%-CI 0.4–2.4). Conclusions: Counselling to women prior to ECV should address the likelihood of success based on the predicting factors described above, as well as the increased risk for OVD in the case of successful ECV.

Does artificial rupturing of membranes in the active phase of labor enhance myometrial electrical activity

Abstract Objective: To determine whether artificial rupture of membranes (AROM) during active phase of labor augments uterine contractility using Electrical Uterine Myography (EUM). Study design: A prospective study of 31 women with term singleton pregnancy during active phase of labor. Using a non-invasive EUM technique, electrical uterine activity was recorded in the 30 min preceding AROM and in the immediate 30 min thereafter. Augmentation was defined as >5% increase in EUM index between the basal and post-AROM states, representing the mean EUM increase of the entire cohort. Low basal uterine contraction was defined as EUM index of less than the entire cohort median result prior AROM (3.5 micro-Watt-Second (mWS)). Results: Mean dilatation in which AROM was preformed was 5.5 ± 1.8 cm. There was a significant increase in mean EUM measurement in the post-AROM compared to the basal state (3.59 ± 0.39 versus 3.42 ± 0.47 mWS, p < 0.001). In multivariate analysis, low BMI and low basal uterine contractions were the only significant predictors for augmentation following AROM (OR 0.69, 95% C.I 0.45–0.97, p = 0.009 and OR 16.03, 95% CI 1.90–134.69, p = 0.003, respectively). Conclusion: Myometrial electrical activity was significantly enhanced following AROM. Augmentation was mostly pronounced in patients with lower BMI and initial lower basal uterine contraction.

Antenatal risk factors for symptomatic congenital CMV disease following primary maternal CMV infection.

Abstract Objectives: This study aimed to evaluate antenatal risk factors associated with symptomatic congenital cytomegalovirus (CMV) disease, following in utero vertical infection. Methods: This study included a retrospective cohort of 155 neonates with congenital CMV infection, following primary maternal CMV infection during pregnancy, and were divided to symptomatic (n=95) and asymptomatic (n=60) newborns. Results: Young maternal age (29.1±5.12 vs. 31.6±5.36 years, P=0.005), high risk occupation for viral exposure (20.0% vs. 11.7%, P=0.04), CMV IgG seroconversion at diagnosis (83.1% vs. 63.3%, P=0.005) and abnormal fetal MRI (11.6% vs. 0%, P=0.003) were found to be prognostic risk factors associated with symptomatic CMV disease of the newborn. Maternal febrile illness at diagnosis, IgG avidity, US findings and the timing of maternal infection were not associated with the occurrence of neonatal symptoms. Conclusions: Knowledge of the reported risk factors may assist in counseling parents with intra uterine CMV infection.

Factors affecting uterine electrical activity during the active phase of labor prior to rupture of membranes.

Abstract Objective: Limited data exist regarding uterine contraction intensity prior to membrane rupture. Using a novel technique of electrical uterine myography (EUM) we aimed to determine which factors affect myometrial activity during active phase of labor. Methods: EUM was prospectively measured in 37 women with singleton pregnancy at term during the active phase of labor until membranes’ rupture. EUM was measured using non-invasive nine channels recorder with an EMG amplifier and three-dimensional position sensor. Uterine electrical activity was quantified with the EUM-index, defined as the mean electrical activity of the uterine muscle over a period of 10 min and measured in units of micro-Joule (microwatt per second [mW/s]). Results: The mean EUM-index at the first 10 min of the measurement was 3.3 ± 0.6 mW/s. In a stepwise linear regression model accounting potential confounders EUM was significantly affected by cervical dilatation (p = 0.005), maternal age (p = 0.04) and previous cesarean delivery status (p = 0.02). In a repeated measurement assessment of non-parametric Fridman’s test for all subjects who had at least 10 continuouss EUM measurements, there was a significant increase in electrical uterine activity as labor progressed (p = 0.01). Conclusion: Electrical uterine activity during the active phase of labor prior to rupture of membranes is affected by maternal age, previous cesarean delivery status and cervical dilatation. Moreover, electrical uterine activity is enhanced throughout labor.

Uterine electric activity during the third stage of labor; a look into the physiology of a deserted stage

Abstract Objective: To evaluate uterine activity during the third stage of labor and compare it to that observed in the second stage of labor. Study design: Uterine electric activity was prospectively measured using electrical uterine myography (EUM) in 44 women with singleton pregnancy at term during the final 30 min of the second stage and throughout the third stage of labor. Results are reported using a scoring index of 1–5 mWS (micro-Watt-Second). Patients were stratified into two groups based on the duration of the third stage (<15 min and >=15 min) Results: The mean durations of the second and third stages were 51.9 ± 63.5 and 15.4 ± 7.5 minutes, respectively. During the third stage, uterine activity (contractions peaks) was similar to that observed during the second stage of labor (3.43 ± 0.64 mWS versus 3.42 ± 0.57 mWS, p = 0.8). No correlation was found between the duration of the third stage and EUM measurements during the third (p = 0.9) or the second (p = 0.2) stages of labor. No association was found between EUM measurements during the third stage and parity, maternal age, fetal weight, duration of labor, gestational age, gravity or BMI. The rate of oxytocin use during the second stage and EUM measurements during the second or third stage did not differ among women with short versus long duration of the third stage. Conclusion: Uterine activity during the third stage is comparable and as intense as that occurring during the second stage. Third stage length cannot be predicted by contraction intensity during the second or third stage of labor.

Uterine electrical activity at labor: is there a correlation between labor stages?

Abstract Objective: To determine the association between the myometrial electrical activity in the active and second stages of labor at term using electrical uterine myography (EUM). Methods: A prospective observational study of 47 singleton deliveries at term in a tertiary hospital. All women were assessed using noninvasive 9-channel surface electrodes of the EUM during labor. EUM index (EUMi) was calculated as the mean electrical activity during a 30 min monitoring period and expressed as microjouls (MJ). Mean EUMi of the active and second stages of labor were compared accordingly. Results: Mean EUMi during the active phase was 3.53 ± 0.43 MJ, whereas mean EUMi in the second stage was 3.66 ± 0.48 MJ (p = 0.02). Correlation analysis between mean EUMi of the active and second stages of labor produced r2 = 0.68 (p < 0.01). In a regression analysis model EUMi of the active stage of labor remained strongly correlated with the duration of the second stage (r2 = 0.73, p < 0.001). No correlation was found between EUMi and the duration of the second stage. Conclusion: A positive correlation of myometrial electrical activity exists between active phase and second stage of labor. However, while EUMi was associated with the duration of the active phase, no correlation was found between EUMi and the duration of the second stage.