Prediction Of Uterine Rupture Research Articles

Transvaginal Ultrasonographic Assessment of Lower Uterine Segment Thickness and Prediction of Uterine Rupture In Cases of Vaginal Birth After Caesarean Delivery

Background: The rise in elective CSs, which make about one-third of all CSs, is primarily to blame for the rise in the Cesarean birth rate. Objective: To assess the strength of the association between transvaginal ultrasonographic measurement of the lower uterine segment in women with prior one CS undergoing a trial of vaginal birth and uterine scar defect at delivery. Patients and Methods: A retrospective observational study was conducted at Al Ahrar Zagazig Teaching Hospital during the period from June 2018 through June 2020. The lower uterine segment thickness was measured transvaginal ultrasonography in 60 gravid as (36 week – 40 week) with previous one CS undergoing VBAC, and the scar was evaluated during delivery. Results: Uterine dehiscence was found in 4 cases (6.7%). There were no cases of uterine rupture. There was significant correlation between the grade of scar and sonographic measurement of LUS thickness using trans-vaginal ultrasound (p value= 0.001).The scar thickness in the third trimester (36-40 week) had a significant relation with the mode of delivery. 2.4 mm was considered the critical cutoff value of the LUS thickness above which safe vaginal delivery can be achieved. This critical cutoff value was derived from the ROC curve with sensitivity, specificity, PPV, and NPV 75.0%, 85.7%, 27.3%, and 98.0%, respectively. Conclusion: Measurement of the lower uterine segment thickness by TVS seems to be a good screening test with its obviously high sensitivity and negative predictive value. LUS thickness of

Can third‐trimester assessment of uterine scar in women with prior Cesarean section predict uterine rupture?

The increasing rate of caesarean delivery is a worldwide concern. A major contributor to this evolution has been a concomitantly decline in vaginal birth after caesarean, because of the risk of intrapartum uterine rupture, which is a rare but potentially catastrophic complication of a trial of labour after caesarean (TOLAC). On the other hand, elective repeat caesarean is associated with surgical complications and risk of abnormal placentation (e.g. placenta accreta) in subsequent pregnancies. Therefore TOLAC is recommended to women with good prognosis of success and low risk of uterine rupture. The published data suggest that sonographic assessment of lower uterine segment in third trimester could potentially play an important role in the prediction of uterine rupture in women with previous caesarean. (Less)

Sonographic Measurement of Lower Uterine Segment Thickness to Predict Uterine Rupture During a Trial of Labor in Women With Previous Cesarean Section

Along with the increasing rate of cesarean section (CS) births has been a concomitant decrease in the rate of vaginal birth after cesarean (VBAC), mostly due to concerns about uterine rupture during a trial of labor (TOL). The risk of uterine rupture in laboring women with a previous CS must be balanced against the increasing current and future risk of peripartum hysterectomy with repeat cesarean. Improved prediction of uterine rupture could allow women at low risk to have a TOL, and those at high risk for uterine rupture could undergo a planned CS. Thinning in the lower uterine segment (LUS) measured by ultrasonography is a possible predictor of uterine rupture. The present study was performed to identify an optimal LUS thickness cutoff value and to define groups of women with a history of previous CS to whom TOL either should not be offered or could be offered safely. PubMed and EMBASE were searched for relevant articles published during 1980 to 2011. Included studies reported on pregnant women with at least 1 prior CS and on the sonographic appearance of the LUS during pregnancy in relation to uterine defects observed during or immediately after delivery. Studies were scored on methodologic and clinical characteristics. For each study, a 2 x 2 table was constructed, cross-classifying LUS thickness measured by ultrasound and the presence of LUS defect after delivery. Sensitivity and specificity were determined for each study in the receiver operating characteristic (ROC) space along with a corresponding summary ROC curve. From an initial 147 citations, 21 studies (all cohort design) were included and involved 2776 women. The median sample size was 71 (range, 10-642; interquartile range, 149.5). Lower uterine segment measurements were obtained at 34 to 39 weeks' gestation. Cutoff values used to define an insufficient LUS ranged from 0.5 to 3.0 mm in studies measuring myometrial LUS thickness and from 1.5 to 5.1 mm in those using full LUS thickness. Full LUS thickness measurement using cutoffs of 2.0 to 3.0 mm had a specificity of 0.91 (95% confidence interval [CI], 0.80-0.96) at a sensitivity of 0.61 (95% CI, 0.42-0.77). Full LUS thickness measurement using cutoffs of 3.1 to 5.1 mm had a specificity of 0.63 (95% CI, 0.30-0.87) at a sensitivity of 0.96 (95% CI, 0.89-0.98). The accuracy of transvaginal or transabdominal sonography could not be compared statistically because of the limited number of studies. The main finding is the strong negative correlation between LUS thickness and risk of uterine defect. The similar shapes of the ROC curves for myometrial and full LUS thickness indicated no significant difference in accuracy, shape, and position. An ideal screening test to predict uterine rupture could affect medical decision making by allowing accurate selection of women with a scarred uterus unlikely to have uterine rupture and thus able to have a TOL

821: Prediction of uterine rupture or dehiscence during trial of labor after cesarean delivery: a cohort study

821: Prediction of uterine rupture or dehiscence during trial of labor after cesarean delivery: a cohort study

Sonography of Lower Uterine Segment Thickness and Prediction of Uterine Rupture

Bergeron, Marie-Eve MD; Jastrow, Nicole MD; Brassard, Normand MD; Girard, Mario RT; Bujold, Emmanuel MD Author Information

Sonography of Lower Uterine Segment Thickness and Prediction of Uterine Rupture

Sonography of Lower Uterine Segment Thickness and Prediction of Uterine Rupture

Sonography of Lower Uterine Segment Thickness and Prediction of Uterine Rupture

Sonographic evaluation of the lower uterine segment was undertaken to study the degree of thinning and, thus, to predict uterine rupture. However, the best measuring technique and recommended cutoff values remain controversial. Sonographic evaluation of the lower uterine segment at 36 weeks of gestation in a 31-year-old patient with prior low transverse cesarean delivery revealed a full thickness of 3.6 mm and a myometrial layer of 1.1 mm. Nevertheless, the patient experienced a large uterine rupture during a trial of labor at term. In this case, there was a discrepancy between the full thickness and the myometrial layer, which could be representative of the lower uterine segment resistance. Such a case emphasizes the need for a consensus on sonographic measuring techniques for the prediction of uterine rupture.

Prediction of uterine rupture associated with attempted vaginal birth after cesarean delivery

Prediction of uterine rupture associated with attempted vaginal birth after cesarean delivery

OC136: Factors influencing the lower uterine segment thickness in late pregnancies with previous Cesarean Section

Objectives: Several studies have shown that sonographic evaluation of the lower uterine segment (LUS) thickness can predict uterine rupture using either the full LUS thickness or the muscular layer measurement. We aimed to evaluate the potential factors associated with LUS thickness. Methods: A prospective cohort study of women with prior cesarean was conducted. Measurements of the LUS thickness were performed transabdominally and repeated transvaginally if unsatisfactory visualised. The thinnest measurement was considered as the dependant variable. Non-parametric analyses were used to evaluate potential factors associated with LUS thickness including: maternal age, gestational age, interdelivery interval, prior vaginal delivery, and characteristics of the prior cesarean section. Multivariate linear regressions were performed to adjust for confounding variables. Results: 252 women were recruited at a mean gestational age of 36.7 ± 1.3 weeks. In univariate analyses, the only significant factor associated with full LUS thickness was the indication of the prior cesarean (recurrent vs. non recurrent: 3.0 InterQuartile (IQ): 2.4–3.8 mm and 2.5 IQ: 2.0–3.2 mm respectively, P < 0.001). For the muscular layer thickness, the indication (recurrent vs. non recurrent: 1.5 IQ: 1.1–2.1 mm and 1.2 IQ: 0.8–1.8 mm respectively, P < 0.001) and the number of closure layers of the previous cesarean (single vs. double layer : 1.1 IQ: 0.8–1.5 mm and 1.4 IQ: 1.0–1.9 mm respectively, P = 0.02) were significant. The indication of the prior cesarean remained the only significant factor in the linear regression model (P = 0.03). Conclusions: We demonstrated an association between non recurrent indications of prior cesarean and thinner LUS near term. Although this factor has never been associated with higher risk of uterine rupture, we need to consider this information in future researches and analyses of LUS thickness for the prediction of uterine rupture.

OC135: Factors associated with lower uterine segment thickness in women with previous cesarean: A prospective study

Objectives: Several studies have shown that sonographic evaluation of the lower uterine segment (LUS) thickness can predict uterine rupture using either the full LUS thickness or the muscular layer measurement. We aimed to evaluate the potential factors associated with LUS thickness. Methods: A prospective cohort study of women with prior cesarean was conducted. Measurements of the LUS thickness were performed transabdominally and repeated transvaginally if unsatisfactory visualised. The thinnest measurement was considered as the dependant variable. Non-parametric analyses were used to evaluate potential factors associated with LUS thickness including: maternal age, gestational age, interdelivery interval, prior vaginal delivery, and characteristics of the prior cesarean section. Multivariate linear regressions were performed to adjust for confounding variables. Results: 252 women were recruited at a mean gestational age of 36.7 ± 1.3 weeks. In univariate analyses, the only significant factor associated with full LUS thickness was the indication of the prior cesarean (recurrent vs. non recurrent: 3.0 InterQuartile (IQ): 2.4–3.8 mm and 2.5 IQ: 2.0–3.2 mm respectively, P < 0.001). For the muscular layer thickness, the indication (recurrent vs. non recurrent: 1.5 IQ: 1.1–2.1 mm and 1.2 IQ: 0.8–1.8 mm respectively, P < 0.001) and the number of closure layers of the previous cesarean (single vs. double layer : 1.1 IQ: 0.8–1.5 mm and 1.4 IQ: 1.0–1.9 mm respectively, P = 0.02) were significant. The indication of the prior cesarean remained the only significant factor in the linear regression model (P = 0.03). Conclusions: We demonstrated an association between non recurrent indications of prior cesarean and thinner LUS near term. Although this factor has never been associated with higher risk of uterine rupture, we need to consider this information in future researches and analyses of LUS thickness for the prediction of uterine rupture.