Lower Uterine Segment Thickness Research Articles

Accuracy of sonographic lower segment thickness and prediction of vaginal birth after caesarean in a resourced-limited setting; Prospective study.

To assess the accuracy of ultrasound measurement of the lower uterine segment (LUS) thickness against findings at laparotomy, and to investigate its correlation with the success rate of vaginal birth after one previous caesarean delivery (CD) in a resource-limited setting. Prospective study. Obstetrics and Gynaecology department in a tertiary hospital in Ghana. Women with one previous CD undergoing either a trial of labour (TOLAC) or elective CD. Myometrial lower uterine segment thickness (mLUS) and full lower uterine segment thickness (fLUS) were measured with transvaginal ultrasound (TVUS). The women were managed according to local protocols with the clinicians blinded to the ultrasound measurements. The LUS was measured intraoperatively for comparison with ultrasound measurements. Lower uterine segment findings at laparotomy, successful vaginal birth. A total of 311 pregnant women with one previous CD were enrolled; 147 women underwent elective CD and 164 women underwent a TOLAC. Of the women that underwent TOLAC, 96 (58.5%) women had a successful vaginal birth. The mLUS was comparable to the intraoperative measurement in the elective CD group with LUS thickness <5 mm (bias of 0.01, 95% CI -0.10 to 0.12 mm) whereas fLUS overestimated LUS <5 mm (bias of 0.93, 95% CI 0.80-1.06 mm). Successful vaginal birth rate correlated with increasing mLUS values (odds ratio 1.30, 95% CI 1.03-1.64). Twelve cases of uterine defect were recorded. LUS measurement ≤2.0 mm was associated with an increased risk of uterine defects with a sensitivity of 91.7% (95% CI 61.5-99.8%) and specificity of 81.8% (95% CI 75.8-86.8%). Accurate TVUS measurement of the LUS is technically feasible in a resource-limited setting. This approach could help in making safer decisions on mode of birth in limited-resource settings.

The utility of combined utero-cervical ındex in predicting preterm delivery in pregnant women with preterm uterine contractions.

To evaluate the utility of a novel ultrasound index "combined utero-cervical index (CUCI)" in the prediction of preterm delivery. The present prospective cohort study was conducted in Ankara Bilkent City Hospital Perinatology Clinic between January 1, 2023, and March 31, 2023. Pregnant women with uterine contractions between 24 and 36th gestational weeks but did not have dilatation or effacement were included. CUCI was calculated as: (utero-cervical angle)/(anterior cervical lip thickness + fundal thickness + lower uterine segment thickness + cervical length). In the presence of cervical funneling, one point was added to the final result. A ROC analysis was conducted to determine the potential of CUCI in predicting delivery <37weeks of gestation, <34weeks of gestation, and <4weeks after the first admission to the hospital for uterine contractions, respectively. Optimal cut-off values of CUCI were found to be 1.4 (67.1% sensitivity, 67.2% specificity) for predicting delivery at <37th weeks, 1.7 (72.7% sensitivity, 65.7% specificity) for predicting delivery at <34th weeks, and 1.4 (62.5% sensitivity, 61.7% specificity) for predicting delivery at <4weeks. CUCI may be used in the prediction of preterm delivery for pregnant women admitted to hospital with preterm uterine contractions.

Lower uterine segment thickness assessed by transvaginal ultrasound before labor induction: reproducibility analysis and relationship with delivery outcome.

To evaluate the reproducibility of lower uterine segment (LUS) thickness measurement before induction of labor (IOL), and to assess the relationship between LUS thickness and IOL outcomes. This was a prospective cohort study of pregnant women undergoing IOL at term, conducted in a single tertiary hospital between July 2014 and February 2017. Women with a singleton pregnancy at ≥ 37 weeks' gestation, with a live fetus in cephalic presentation and a Bishop score of ≤ 6, were eligible for inclusion. Both nulliparous and parous women, and those with a previous Cesarean section (CS), were eligible. All women underwent transvaginal ultrasound assessment before IOL admission, and cervical length and LUS thickness were measured offline after delivery. Maternal and obstetric characteristics and Bishop score were recorded. The main outcome was the overall rate of CS after IOL, and secondary outcomes were CS for either failure to progress in the active phase of labor or failed IOL, and CS for failed IOL only. Interobserver agreement for measurement of LUS thickness between two operators was assessed using the intraclass correlation coefficient (ICC) and Bland-Altman analysis with the ANOVA test to evaluate systematic bias. Univariable and multivariable analysis were employed to evaluate the relationship between clinical and sonographic characteristics and IOL outcomes. Of 265 women included in the analysis, 195 (73.6%) had a vaginal delivery and 70 (26.4%) required a CS after IOL. Reproducibility analysis showed excellent interobserver agreement for the measurement of LUS thickness (ICC, 0.96 (95% CI, 0.93-0.98)). On Bland-Altman analysis, the mean difference in LUS thickness between the two operators was 0.15 mm (95% limits of agreement, -1.84 to 2.14 mm), and there was no evidence of systematic bias (ANOVA test, P = 0.46). Univariable analysis showed that LUS thickness was associated significantly with overall CS (P = 0.002), CS for failure to progress in the active phase of labor or failed IOL (P = 0.03) and CS for failed IOL (P = 0.037). On multivariable logistic regression analysis, LUS thickness was an independent predictive factor for overall CS (odds ratio (OR), 1.149 (95% CI, 1.031-1.281)) and CS for failure to progress in the active phase of labor or failed IOL (OR, 1.226 (95% CI, 1.039-1.445)). In women undergoing IOL at term, measurement of LUS thickness is feasible and reproducible, and is associated significantly with IOL outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Measurement of Lower Uterine Segment Thickness to Detect Uterine Scar Defect: Comparison of Transabdominal and Transvaginal Ultrasound.

Lower uterine segment (LUS) thickness measurement using transabdominal ultrasound (TA-US), transvaginal ultrasound (TV-US), or the combination of both methods can detect scar defect in women with prior cesarean. We aimed to compare the sensitivity of three approaches. Women with prior cesarean underwent LUS thickness measurement at 34-38 weeks' gestation. Among those who underwent repeat cesarean before labor, we compared the accuracy of TA-US, TV-US, and the thinner of the two measurements (the "combined measurement") for uterine scar dehiscence using the area under the curve (AUC) of receiver operating curves with their 95% confidence intervals (CI). We calculated the sensitivity and specificity of the three approaches using a cut-off of 2.3 mm based on prior literature. We included 747 participants. The mean LUS thickness was greater with TA-US (3.8 ± 1.6 mm) compared with TV-US (3.5 ± 1.9 mm) or the combined measurement (3.2 ± 1.5 mm; P < .001). The AUC was 78% (95% CI: 69%-87%), 85% (95% CI: 79%-91%), and 88% (95% CI: 82%-93%), respectively (all with P < .001). The AUC difference between TA-US and the combined measurement was not significant (P=.057). A LUS below 2.3 mm would have predicted 9 (45%) of the 20 cases of uterine scar dehiscence using TA-US, 17 (85%) using TV-US, and 18 (90%) using the combined measurement (P < .01). The choice of ultrasound approach influences the measurement of the LUS thickness. The combination of the TA-US and TV-US seems to be superior for the detection of uterine dehiscence.

Lower uterine segment thickness is assessed by ultrasound in individuals who have had prior caesarean sections

Introduction: The increased number of caesarean births is causing a great deal of professional and public worry. Using transvaginal and abdominal ultrasonography, estimate the critical thickness over which a safe vaginal birth is foreseeable in women who have previously had caesarean delivery. Method: 50 pregnant women who had previously had a caesarean section served as the case group in a case-control research, whereas 50 pregnant women who had never undergone a caesarean section served as the control group. The gestational age was between 38 and 40 weeks. The thickness of the LUS was measured using TA and TV ultrasonography in both groups; in the study group, a thickness of >2 mm was regarded as good healing and a thickness of 2 mm as poor healing; the mode of delivery for women was either trial VBAC (unless an obstetrical indication for CS existed) or ERCS. There was a correlation between U/S measures and every intraoperative LUS manifestation and delivery result. Result: The total VBAC success rate was 52%, the incidence of dehiscence was 4%, and there was no uterine rupture. The overall VBAC success rate was 84%. Between TA and TV ultrasonography, there was a 95% correlation. The ROC curve's crucial cut off value for safe LUS thickness was 2.5mm. Conclusion: In women who have had a prior caesarean section, sonography enables a reliable measurement of the LUS thickness, making it theoretically possible to utilise it to foretell the risk of uterine rupture during a trial vaginal delivery.

Analysis of Maternal and Infant Outcomes and Related Factors of Vaginal Delivery of Second Pregnancy after Cesarean Section.

Objective To explore the clinical effect of different delivery methods and the safety of vaginal delivery of second pregnancy after cesarean section and analyze the related factors. Methods A total of 738 eligible pregnant women who underwent cesarean section from September 2018 to August 2020 were randomly selected from our hospital. Among them, 527 pregnant women successfully delivered vaginally were selected as the observation group, and 211 pregnant women who failed vaginal delivery were selected as the control group. To analyze the factors that influence the success of vaginal delivery of second pregnancy after cesarean section and compare the outcomes of mother and infant in two groups. Results There was no significant difference in age, prenatal body mass index (BMI), and thickness of lower uterine segment between the two groups (P > 0.05). There were significant differences in fetal head orientation, fetal abdominal circumference, fetal biparietal diameter, uterine height, premature rupture of membranes, Bishop score, and epidural anesthesia during labor between the two groups (P < 0.05). Multivariate logistic regression analysis showed that fetal abdominal circumference, fetal head orientation, Bishop score, and epidural anesthesia during labor were independent factors affecting the success of VBAC (P < 0.05). There was no significant difference in the incidence of uterine rupture between the two groups (P > 0.05). The amount of postpartum hemorrhage in the observation group was significantly lower than that in the control group (P < 0.05). There was no significant difference in Apgar score, asphyxia rate, and hospitalization rate between the two groups (P > 0.05). There was no significant difference in the incidence of complications between the two groups (P > 0.05). Conclusion There are many factors that influence the success of vaginal delivery after cesarean section. Through prenatal comprehensive evaluation of vaginal delivery conditions, we can guide the parturient to choose a reasonable mode of delivery, reduce the incidence of complications, and improve the outcome of mother and baby.

OP08.07: Lower uterine segment thickness in pregnancy following Caesarean section with double layer barbed fish‐bone suture

OP08.07: Lower uterine segment thickness in pregnancy following Caesarean section with double layer barbed fish‐bone suture

Prediction and analysis of adverse pregnancy outcomes in pregnant women with cesarean scar diverticulum

Objective: To investigate the pregnancy outcomes of pregnant women with cesarean scar diverticulum (CSD) and to find the relevant factors that predict the occurrence of adverse pregnancy outcomes. Methods: From January 2015 to March 2019, 501 singleton pregnant women with a history of cesarean section who underwent regular prenatal examination in early pregnancy and eventually delivered in Peking University First Hospital were prospectively collected. According to the presence or absence of CSD in the first trimester of pregnancy, the pregnant women were divided into the CSD group (n=127, 25.3%) and the non-CSD group (n=374, 74.7%). According to the mode of delivery and the classification of the lower uterine segment seen during cesarean section, the CSD group was further divided into the non-rupture group (including spontaneous delivery and lower uterine segment grade Ⅰ;n=108, 85.0%) and rupture group (including lower uterine segment grade Ⅱ-Ⅳ;n=19, 15.0%). The general clinical data, pregnancy outcomes, diverticulum-related indexes [including length, width, depth (D), average diameter, volume, and residual myometrial thickness (RMT)] were compared. The predictive values of D/adjacent myometrial thickness≥50%, RMT≤2.2 mm and D/RMT>1.3 for uterine rupture in CSD pregnant women were verified. Results: (1) Comparison between CSD group and non-CSD group: the lower uterine segment thickness in the third trimester of pregnancy in the CSD group was lower than that in the non-CSD group [(1.2±0.5) vs (1.4±0.6) mm, respectively], and the incidence of uterine rupture was higher than that in the non-CSD group [15.0% (19/127) vs 8.0% (30/374), respectively], and the differences were statistically significant (both P<0.05). There were no significant differences in other clinical data and pregnancy outcomes between the two groups (all P>0.05). (2) Comparison of rupture group and non-rupture group: the lower uterine segment thickness in the third trimester of pregnancy in rupture group [(0.6±0.5) mm] was lower than that in non-rupture group [(1.2±0.6) mm], and the difference was statistically significant (t=3.486, P=0.001). There were no significant differences in diverticulum-related indexes between the two groups (all P>0.05). (3) Relationship between high risk predictors of uterine rupture and actual uterine rupture: the sensitivity of D/adjacent muscle thickness ≥50%, RMT≤2.2 mm and D/RMT>1.3 in predicting the high risk of uterine rupture were 94.7%, 57.9% and 73.6%, the specificity were 12.0%, 40.7% and 24.1%, the positive predictive value were 15.9%, 14.7%, 14.6%, and the negative predictive value were 92.8%, 84.6%, 83.9%, respectively. Conclusions: The risk of uterine rupture in pregnant women with CSD is higher than that in those without CSD. There is no significant correlation between CSD related indexes and uterine rupture in the first trimester. Monitoring the lower uterine segment thickness in the third trimester might be helpful to predict the occurrence of adverse pregnancy outcomes.

Prediction of uterine dehiscence via machine learning by using lower uterine segment thickness and clinical features

With the global increase of cesarean delivery rates, the long-term effects of cesarean delivery have started to become clearer. One of the most prominent complications of cesarean delivery in recurrent pregnancies is uterine rupture. Assessing the risk of uterine rupture by accurately predicting dehiscence is very important to prevent untimely operations and/or maternal and fetal complications. This study aimed to assess whether machine learning can be used to predict uterine dehiscence by using patients' ultrasonographic findings, clinical findings, and demographic data as features. Hence, we investigated a potential method for preventing uterine rupture and its maternal and fetal complications. The study was conducted on 317 patients with term (>37 weeks' gestation) singleton pregnancies and no medical complications or medications that may affect uterine wound healing. Demographics, body mass indices, smoking and drinking habits, clinical features, past pregnancies, number and history of abortions, interdelivery period, gestational week, number of previous cesarean deliveries, fetal presentation, fetal weight, tocography data, transabdominal ultrasonographic measurement of lower uterine segment full thickness and myometrium thickness, and lower uterine segment findings during cesarean delivery were collected and analyzed using machine learning techniques. Logistic regression, multilayer perceptron, support vector machine, random forest, and naive Bayes algorithms were used for classification. The dataset was evaluated using 10-fold cross-validation. Correct classification rate, F-score, Matthews correlation coefficient, precision-recall curve area, and receiver operating characteristic area were used as performance metrics. Among the machine learning techniques tested in this study, the naive Bayes algorithm showed the best predictive performance. Among the various combinations of features used for prediction, the essential features of parity, gravidity, tocographic contraction, cervical dilation, dilation and curettage, and sonographic thickness of lower uterine segment myometrium yielded the best results. The second-best performance was achieved with sonographic full thickness of lower uterine segment added to the base features. The base features alone could classify patients with 90.5% accuracy, whereas adding the myometrium measurement increased the classification performance by 5.1% to 95.6%. Adding the full thickness measurement to the base features raised the classification performance by 4.8% to 95.3% in terms of correct classification rate. The naive Bayes algorithm can correctly classify uterine dehiscence with a correct classification rate of 0.953, an F-score of 0.952, and a Matthews correlation coefficient value of 0.641. This result can be interpreted as indicating that by using clinical features and lower uterine segment ultrasonography findings, machine learning can be used to accurately predict uterine dehiscence.

Intrapartum ultrasound measurement of the lower uterine segment thickness in parturients with previous scar in labor: a cross-sectional study

BackgroundThere is a lack of reliable methods to estimate the risk of uterine rupture or dehiscence during a trial of labor in women with previous cesarean sections. This study aimed to assess the lower uterine segment and myometrial thickness by ultrasonography in women with previous cesarean sections during labor and assess their association with the uterine defect.MethodsA cross-sectional study was conducted on 161 women in the active phase of labor having one previous cesarean section. The study was conducted et al.-Azhar University Hospital, Assiut City, Egypt, from March 2018 to March 2019. Ultrasound measurements of lower uterine segment thickness and myometrial thickness were conducted by vaginal and abdominal ultrasound by two observers. The correlation of both thicknesses with the uterine defect was analyzed.ResultsUterine defects were reported in 42 women (25.9%), uterine rupture in four women (2.5%), and dehiscence in 38 women (23.5%). The uterine defects were not associated with maternal factors (maternal age, gestational age at labor, body mass index, birth weight, interpregnancy, and inter-delivery interval). Receiver operating curve analysis demonstrated that lower uterine segment thickness was linked with uterine defect, with an area under the curve of 60% (95% CI, 51–70%, P = 0.044). Myometrial thickness was also linked to the uterine defect, with an area under the curve of 61% (95% CI, 52–71%, P = 0.025). Full lower uterine segment thickness of 2.3 mm and myometrial thickness of 1.9 mm were the cutoff value with the best combination of sensitivity and specificity for the uterine defect. Lower uterine segment thickness (OR = 0.49, 95%CI 0.24–0.96) and myometrial thickness (OR = 0.44, 95%CI 0.20–0.94) were significantly associated with the uterine defect. Lower uterine segment thickness (OR = 0.41, 95%CI 0.22–0.76) and myometrial thickness (OR = 0.33, 95%CI 0.16–0.66) were also significantly associated with cesarean section delivery.ConclusionA lower uterine segment thickness of 2.3 mm and myometrial thickness of 1.9 mm during the first stage of labor are associated with a high risk of uterine defects during a labor trial. These measurements during labor can have a practical application in deciding the mode of delivery in women with previous cesarean sections and might reduce uterine rupture.

Two dimension versus three dimension ultrasound assessment of caesarean section scars

Background: Ultrasound (US) is now used as an imaging modality for the evaluation of lower uterine segment (LUS). A number of reports of sonographic evaluation of LUS have appeared in literature. It has been speculated that thickness of the LUS is related to the quality of wound healing. There is strong correlation between the anatomic status of scarred LUS as assessed by USG and its functional status which is tested during labour. Objective: The aim of this work was to investigate the accuracy of two-dimensional and three-dimensional ultrasound in measurement of Caesarean section scar thickness. Patients and methods: This study was cross sectional study, conducted in Aswan University Hospital. The ultrasound examinations were conducted in the Obstetrics and Gynecology department between June 2017 and September 2021. The study included 150 pregnant females with previous one or two cesarean sections (CS) (aged 20-41y; mean 32.5y), underwent TA 2D and 3D US for assessment of the LUS thickness at 37-39 gestational weeks, before planning.

The Overlooked Impact of Lower Uterine Segment Contractions on Second Trimester Cervical Assessment

Introduction: Asymptomatic contractions in the lower uterine segment (LUS) may affect uterocervical angle and cervical length (CL); however, this has never been investigated. Therefore, the aim of this study was to evaluate the effect of LUS contractions on uterocervical angle, CL, and LUS thickness. Materials and Methods: This was a prospective, observational, single-cohort study conducted on 102 asymptomatic singleton pregnancies between 19.0 and 22.6 weeks of gestation. Uterocervical angle and CL were measured by transvaginal ultrasound at two different time points with an interval of at least 20 min. LUS thickness was also measured as an indirect marker of myometrial contraction. A linear and curvilinear regression were performed to explore a potential association between LUS contractions, measured as increments in LUS thickness, and changes in CL and uterocervical angle. Results: The linear regression between changes in LUS thickness and changes in CL showed that LUS contractions impact CL; for every 1-mm increase in LUS thickness, CL increased by 0.909 mm, when the isthmus was included in the CL measurement (R² = 0.358; β = 0.909; p < 0.001). By contrast, when the isthmus was not included in the measurement, a curvilinear relation between changes in LUS thickness and changes in CL was found (R² = 0.077; β1 = 0.575, β2 = 0.038; p = 0.018). The relation between changes in uterocervical angle and changes in LUS thickness was not significant. Discussion/Conclusion: LUS contractions can be observed in many asymptomatic women during the second trimester of pregnancy. LUS contractions lead to an increase in CL and LUS thickness, thus impacting ultrasound cervical assessments. These contractions do not affect the uterocervical angle.

Impact of Third-Trimester Measurement of Low Uterine Segment Thickness and Estimated Fetal Weight on Perinatal Morbidity in Women With Prior Cesarean Delivery.

This study aimed to estimate the impact of third-trimester ultrasound with measurement of the lower uterine segment thickness (LUST) and estimation of fetal weight (EFW) on maternal and perinatal morbidity among women with a prior cesarean delivery. We performed a secondary analysis of the QUARISMA trial, including women who delivered at term after one prior cesarean delivery in tertiary care centres. Major and minor maternal and perinatal morbidities were compared between centres that had introduced LUST and EFW measurements into routine practice and those that had not, using generalised estimating equations and adjusted odds ratios (aOR). In a secondary analysis, we compared women who underwent a trial of labour with and without LUST and EFW measurements. We observed a significant reduction in major perinatal morbidity (aOR 0.52; 95% CI 0.28-0.96, P=0.04), minor perinatal morbidity (aOR 0.49; 95% CI 0.25-0.96, P=0.04), and minor maternal morbidity (aOR 0.56; 95% CI 0.34- 0.94, P=0.03) but no significant difference in major maternal morbidity (aOR 0.40; 95% CI 0.04-3.69, P=0.42) in the 2 centres that had introduced third-trimester ultrasound with EFW and LUST measurements (1458 women), compared with the 4 centres (1247 women) that had not. Among women who underwent a trial of labour, we observed a reduction in major perinatal morbidity (aOR 0.25; 95% CI 0.11-0.54, P < 0.001) and a lower rate of uterine rupture (0% vs. 0.3%, P=0.045) with LUST and EFW measurements. Third-trimester ultrasound with EFW and LUST measurement is associated with a significant reduction in major perinatal morbidity in women with a prior cesarean delivery.

Transabdominal versus transvaginal ultrasound to assess the thickness of lower uterine segment at term in women with previous cesarean section

ObjectiveThis study aims to compare transvaginal (TVS) and transabdominal (TAS) ultrasonography precision in to evaluate the lower uterine (LUS) thickness in women with a previous Cesarean section at the term pregnancy; to be an effective method for assessment of previous cesarean scar strength. Material and methodsAn observational cross-sectional study was conducted at kasr el-ainy Hospital in Egypt. From May to November 2020, we admitted 130 pregnant women at term with a previous cesarean section for an elective cesarean delivery. Lower uterine segment thickness was obtained using both transvaginal ultrasound and transabdominal ultrasound before the cesarean. The exact thickness of the lower uterine segment was recorded using a sterile metal ruler before the neonate had been delivered. ResultsThe mean thickness of the lower uterine segment obtained by transabdominal ultrasound was 5.2 ± 1.6 mm and 4.8 ± 1.33 mm by transvaginal ultrasound, then compared each of them to the mean actual thickness, which was 4.5 ± 1.22 mm. The lower uterine segment thickness with transabdominal ultrasound showed a good correlation (r = 0.722) with the actual thickness, the correlation with transvaginal ultrasound was better (r = 0.944). A cut-off value transvaginal ultrasound of 3.65 mm with 90.8% sensitivity and 65.6% specificity. ConclusionTransvaginal ultrasound is more accurate in assessing the thickness of the lower uterine segment than transabdominal ultrasound. A total lower uterine segment thickness of <3.65 is considered a thin scar, and <2.85 mm is associated with a higher risk of uterine dehiscence.The trial was registered in ClinicalTrials.gov registry with clinical trial. https://clinicaltrials.gov/ct2/show/NCT04687891.

Transabdominal and transvaginal ultrasonographic assessment of lower uterine segment thickness in pregnant women before repeat cesarean section

Transabdominal and transvaginal ultrasonographic assessment of lower uterine segment thickness in pregnant women before repeat cesarean section

Lower Uterine Segment Ultrasound Among Individuals with Prior Cesarean: A Cost-Effectiveness Analysis

Patients with a history of cesarean delivery (CD) do not always attempt trial of labor after cesarean (TOLAC) due to risk of adverse outcomes. A recent meta-analysis demonstrated the efficacy of using ultrasound to screen for lower uterine segment thickness (LUS) at a threshold of 3.65 mm to stratify risk of individuals with a prior CD. Individuals < 3.65 mm are advised to undergo CD, while those above ≥3.65 mm may attempt TOLAC. This study evaluated the cost-effectiveness of LUS screening for patients who wish to TOLAC.

Changes in lower uterine segment thickness during different gestational weeks in pregnant women qualified for trial of labor after cesarean section.

ObjectiveTo investigate the correlation between lower uterine segment thickness (LUST) and gestational weeks (GW) in women who attempted trial of labor after cesarean section (TOLAC) and to estimate the reference ranges of LUST.MethodsA prospective cohort study was conducted between January 2019 and December 2020 at a tertiary‐care center in Foshan, China. A total of 2588 women who attempted TOLAC were included. LUST was measured in different trimesters using transabdominal ultrasound. Histograms were used to review the mean and standard deviations (SD) of LUST at different GW.ResultsThe mean LUST of the patients were 6.90 ± 2.86, 4.36 ± 1.87, 2.83 ± 0.65, and 2.57 ± 0.51 mm in the first (12.10 ± 1.28 weeks), second (21.79 ± 3.40 weeks), middle third (34.28 ± 2.64 weeks), and late third (38.20 ± 1.00 weeks) trimesters, respectively. An inverse correlation was noted between LUST and uterine rupture in women who underwent a planned ERCD (P < 0.001), but not in women who attempted TOLAC during the late third trimester (P = 0.629).ConclusionLUST is inversely correlated with GW and decreases faster in the first and second trimesters than in the middle and late third trimesters. TOLAC should be approached with caution for pregnant women with a thin myometrium in late third trimester.

Sonographic Lower Uterine Segment Thickness to Predict Cesarean Scar Defect in Pregnant Women

Objective: To study the validity of sonographic lower uterine segment (LUS) thickness in predicting intraoperative cesarean scar defect (CSD) and thin incision sites in term pregnancy. Methods: This was a cross-sectional study involving 111 full-term pregnant women who were scheduled for repeat cesarean delivery from April, 2019 to January, 2020. The sonographic myometrial LUS thickness was measured prior to surgery. The cesarean scar was assessed using the morphologic classification system as either grade 1 (a normally formed LUS), grade 2 (a thin LUS, but without visible content), or grade 3 (a thin LUS with visible content). Then, the ophthalmic caliper was used to measure the incision site’s uterine-wall thickness. The correlations between the sonographic measurements and intraoperative findings were reported. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated.Results: There were two cases (1.8%) of grade 3 CSD. The overall correlation between the sonographic and intraoperative incision-site thickness showed r=0.559 with p-value &lt; 0.001. The sonographic cut-off value of 1.5 mm could predict CSD and a thin incision-site uterine wall with sensitivity, specificity, PPV, NPV of 50.0%, 90.8%, 9.1%, 99.0%, and 37.5%, 94.6%, 54.5%, 90.0%, respectively. A receiver operating characteristic curve was generated to determine the optimum cut-off value at 2.5 mm with a sensitivity of 76.5% and a specificity of 73.3%. The area under the curve was 0.8 (a 95% confidence interval, 0.718-0.885).Conclusion: Abdominal sonography is a valuable tool for the preoperative prediction of CSD. A myometrial LUS thickness of more than 1.5 mm is associated with a lower likelihood of cesarean scar dehiscence.

Ultrasonographic assessment of lower uterine segment thickness and perinatal Outcomes in patients with a previous cesarean history

Objective: The purpose of the study was to establish the validity of the abdominal evaluation of lower uterine segment (LUS) thickness in patients having a previous cesarean section (CS) in predicting uterine rupture, and to evaluate if there is any effect of the number of a previous surgeries on adverse maternal and perinatal outcomes.&#x0D; Materials and methods: A prospective case-control study was carried out between December 2017 and June 2018 in Dr. Zekai Tahir Burak Women’s Health Education and Research Hospital. 555 patients were classified into three groups; Group 1: patients having one previous CS, Group 2: patients having two previous CS, Group 3: patients having more than the two previous CS). Ultrasonographic measurements of the LUS, intraoperative findings and, adverse pregnancy outcomes were assessed.&#x0D; Results: LUS thickness of group 2 was significantly less than the LUS thickness of the other groups (p=0.022). The feeling of pain was significantly more in the patients of group 2, when compared with the other groups (p=0.019). Pregnancy interval was the only parameter that had significant predictivity for adverse pregnancy outcomes for group 1(#CS=2) and group 3 (#CS≥4) (p=0.042, and p=0.021, respectively). In group 2 (#CS=3), age, the thickness of LUS, and thickness of subcutaneous adipose tissue were found to have significantly high predictivity for adverse pregnancy outcomes (p=0.012, p≤0.001, and p=0.007, respectively).&#x0D; Conclusion: Measurement of LUS, in the patients who had previous CS, can be used for risk assessment and management. It is a non-invasive, reliable and, easily applicable method. Standardization of the measurement technique is a necessity.

Ultrasonic assessment has high sensitivity for pregnant women with previous cesarean section occurring uterine dehiscence and rupture: A STARD-compliant article.

To investigate the diagnostic performance of ultrasound (US) for pregnant women with previous caesarean section (CS) occurring lower uterine segment (LUS) dehiscence and rupture.107 pregnant women with previous CS and LUS thickness of 1.0 mm or less were recruited, the LUS and myometrium was measured, and US findings suggestive of uterine rupture were compared with findings at laparotomy. The included pregnant women were assigned into 2 groups, including 64 pregnant women had vaginal delivery at full-term and 43 pregnant women underwent repeat CS at preterm.US findings suggestive of uterine rupture and dehiscence occurred in 18 women and 89 women, respectively; ten of them developed uterine rupture, and the incidence of uterine rupture was 9.34% (10/107). The sensitivity, specificity, accuracy, positive, and negative predictive values of US for the evaluation of LUS dehiscence and rupture were 100.0%, 91.8%, 92.5%, 55.6%, and 100.0%, respectively. There was no severe maternal obstetric complication, 1 fetus died, and the other fetuses were born with a 5-minute Apgar score of 7 to 10.US has high sensitivity and specificity for pregnant women with previous CS occurring LUS dehiscence and rupture.