Sonographic Measurement Of Cervical Length Research Articles

Preterm Birth: Screening and Prediction.

Preterm birth (PTB) affects approximately 10% of births globally each year and is the most significant direct cause of neonatal death and of long-term disability worldwide. Early identification of women at high risk of PTB is important, given the availability of evidence-based, effective screening modalities, which facilitate decision-making on preventative strategies, particularly transvaginal sonographic cervical length (CL) measurement. There is growing evidence that combining CL with quantitative fetal fibronectin (qfFN) and maternal risk factors in the extensively peer-reviewed and validated QUanititative Innovation in Predicting Preterm birth (QUiPP) application can aid both the triage of patients who present as emergencies with symptoms of preterm labor and high-risk asymptomatic women attending PTB surveillance clinics. The QUiPP app risk of delivery thus supports shared decision-making with patients on the need for increased outpatient surveillance, in-patient treatment for preterm labor or simply reassurance for those unlikely to deliver preterm. Effective triage of patients at preterm gestations is an obstetric clinical priority as correctly timed administration of antenatal corticosteroids will maximise their neonatal benefits. This review explores the predictive capacity of existing predictive tests for PTB in both singleton and multiple pregnancies, including the QUiPP app v.2. and discusses promising new research areas, which aim to predict PTB through cervical stiffness and elastography measurements, metabolomics, extracellular vesicles and artificial intelligence.

OC13.04: Can sonographic cervical length measurements predict preterm birth in triplet pregnancies?

OC13.04: Can sonographic cervical length measurements predict preterm birth in triplet pregnancies?

The effectiveness of vaginal progesterone in reducing preterm birth in high-risk patients diagnosed with short cervical length after 24 weeks: A retrospective cohort study.

To assess the impact of progesterone treatment on maternal and neonatal outcomes in women with a history of preterm birth and short cervical length diagnosed after 24 weeks of gestation. A retrospective cohort study included women with a history of preterm birth and a transvaginal sonographic cervical length measurement of ≤ 25 mm, diagnosed between 24+0 and 33+6 weeks of gestation. Exclusion criteria included prior progesterone treatment, cervical cerclage, or pessary. The study population was divided into the progesterone treatment group and the non-treatment group. The study included 104 women, with 46.2% (48/104) receiving progesterone treatment and 53.8% (56/104) not receiving treatment. The rate of spontaneous preterm birth before 37 weeks of gestation was 43% (24/56) in the non-treatment group and 31% (15/48) in the progesterone treatment group (P = 0.14); the rate of spontaneous preterm birth before 34 weeks was 7% (4/56) in the non-treatment group and 0% (0/48) in the progesterone treatment group (P = 0.05). Progesterone treatment was associated with a significant decrease in neonatal intensive care unit admissions (OR 0.20, 95% CI 0.05-0.74) and in the neonatal hospitalization period (mean difference in days 2.43, 95% CI 0.44-4.42). The risk of recurrent spontaneous preterm birth was highest (71%) among women with two or more previous preterm deliveries who did not receive progesterone treatment, and lowest (24%) among women with one previous preterm delivery who received progesterone treatment. Progesterone treatment was associated with a reduction in rates of spontaneous preterm birth before 34 weeks of gestation, neonatal intensive care unit admission, and neonatal length of stay in high-risk patients, even when initiated after 24 weeks of gestation.

The Association between Cervical Length and Successful Labor Induction: A Retrospective Cohort Study.

This study aimed to determine whether transvaginal sonographic measurement of cervical length before labor induction can predict successful induction. This retrospective study recruited 138 pregnant women who underwent labor induction at 37-41 weeks of gestation. Cervical length was measured using transvaginal ultrasonography before labor induction. Labor was induced according to the hospital protocol. Age, gestational age (GA), parity, body mass index (BMI), Bishop score, hemoglobin level, maternal disease, and epidural anesthesia were also recorded. Labor induction outcomes, including cesarean section for failed induction, time of induction, and the three labor stages, were assessed. From December 2018 to December 2021, 138 women were recruited for our study, including 120 and 18 women with successful and failed labor induction, respectively. Shorter cervical length (≤3.415 cm, OR = 6.22, 95% CI = 1.75-22.15) and multiparity (OR = 17.69, 95% CI = 2.94-106.51) were associated with successful induction. Higher BMI was associated with failed induction (OR = 0.87, 95% CI = 0.75-0.99). Age, GA, Bishop score, and fetal birth weight were not associated with successful labor induction. The ROC curve showed a cervical length cutoff value of 3.415 cm, revealing 76.8% of the area under the curve. In conclusion, a shorter cervical length (≤3.415 cm) was associated with a higher chance of successful labor induction (76.8%). This parameter might be used to predict the chance of successful labor induction. This information could help better inform clinician discussions with pregnant women concerning the chance of successful labor induction and consequent decision-making. Nevertheless, further large-scale clinical trials are warranted.

“Bishop has left the building”-a randomized controlled trial to determine our modern induction needs

To compare the prediction value of full Bishop score to a “modified” Bishop score and cervical length measured by transvaginal sonography in nulliparous patients undergoing induction of labor at term. A prospective randomized controlled trial of patients admitted for labor induction at term at a single tertiary center between January 2019-December 2021. Patients were randomly assigned to one of the following groups: 1) induction based on full Bishop score; 2) induction based on cervical dilation and effacement alone (“modified” Bishop score); 3) induction based on sonographic cervical length measurements. We excluded patients from the final analysis if they were in active labor pre-induction, had a full Bishop score >5, >2 cm dilation or >80% effacement (“modified” Bishop score), or a cervical length< 20 mm, accordingly. The primary outcome was the rate of vaginal delivery. Secondary outcomes included induction to delivery interval, additional labor augmentation, pain assessment, and adverse maternal and neonatal outcomes. The final analysis included 758 patients. Vaginal delivery rate was similar in all three groups (84% vs. 81% vs 83%, P=0.68), along with the need for additional augmentation, and induction to delivery interval (71.4% vs. 72.3% vs. 70.3%, P=0.35, and 25.6±4.9 vs. 26.3±4.4 vs. 25.5±4.8, P=0.26, respectively). There were no significant differences in adverse maternal or neonatal outcomes between the groups. All 3 methods were similar as predictors of induction success (area under the curve 0.611 vs. 0.607 vs 0.615, P=0.023 vs. P=0.019 vs. P=0.017, respectively) with no significant difference between in test properties including sensitivity, specificity, positive and negative predictive values. Visual analogue scores were similar between the 3 tests (P=0.66). In nulliparous patients undergoing induction of labor, evaluating dilation and effacement alone is as efficient as full Bishop score or sonographic cervical length measurement in prediction of vaginal delivery success and induction to delivery interval with no significant difference in pain level.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Cervical Length Measurement at Term Pregnancy as a Predictor of Time of Onset of Labour and Mode of Delivery: A Longitudinal Study

Introduction: Cervical assessment has moved from digital examination to sonographic evaluation in recent years. Predicting the time of onset of labour and mode of delivery at term is a great concern for both the pregnant woman and her relatives. Aim: To predict the time of onset of labour and mode of delivery by Transvaginal sonographic measurement of cervical length at term. Materials and Methods: This longitudinal study was conducted in the Department of Obstetrics and Gynaecology, SRM Medical College Hospital and Research Centre, Kattankalathur, Tamil Nadu, India, from March 2021 to August 2021. All low-risk singleton pregnancies between 38-40 weeks of gestation were included. Cervical length (in mm) was measured transvaginally by the principal investigator between 38 and 40 weeks. When the labour sets in the duration between cervical length measurement and the onset of labour, duration of labour and mode of delivery were noted. Pearson correlation coefficient was used to quantify the association between cervical length and time of onset of labour and duration of labour. Results: In the study, 164 low-risk patients (143 Primigravida patients+21 Multigravida patients) between 38-40 weeks were included. In patients with spontaneous onset of labour, 45 (70.3%) had labour onset within 120 hours (5 days) when cervical length was ≤30 mm, when compared with 7 (22.58%) when cervical length was &gt;30 mm (p=0.001). In patients with cervical length ≤30 mm, vaginal delivery occurred in 47 (73.43%) (p=0.019). In women with induced labour with cervical length ≤30 mm, 13 (61.9%) had labour onset within 120 hours when compared to 15 (30.6%) in women with cervical length &gt;30 mm (p=0.02). Vaginal delivery occurred in 5 (29.41%) of women when cervical length was ≤30 mm compared to 32 (65.30) in women when cervical length &gt;30 mm which may be attributed to other causes. There was a significant positive correlation between cervical length and time of onset of labour (Correlation coefficient=0.221, p-value=0.004). There was a negative correlation between cervical length and duration of labour which was not statistically significant (Correlation coefficient=-0.108, p=0.25). There was no significant difference in mean cervical length measurement between vaginal delivery and caesarean section. Conclusion: Transvaginal cervical length measurement at term positively correlates with time of onset of labour but not with duration of labour and mode of delivery

The predictive role of second trimester uterocervical angle measurement in obstetric outcomes.

Objective:Uterocervical angle has been suggested as a marker to predict preterm birth. However, the literature has limited data about its predictive role in preterm delivery. Moreover, no evidence is present to clarify the role of second-trimester uterocervical angle in induction success and postpartum hemorrhage. Here, it was aimed to compare the role of uterocervical angle with cervical length in predicting preterm labor and assess the utility of the second-trimester uterocervical angle in induction success and postpartum hemorrhage.Materials and Methods:A total of 125 pregnant women, hospitalized with a diagnosis of preterm labor were included in the study. Sonographic measurements of cervical length and uterocervical angle were performed between 16 and 24 weeks of gestation. The demographic, obstetric, laboratory, and sonographic features of the participants were recorded. Patients were divided into subgroups as preterm and term; with and without induction success; with and without postpartum hemorrhage. Additionally, preterm cases were divided into subgroups as early and late preterm. Variables were evaluated between the groups.Results:Cervical length was shorter in the preterm group (30.74±6.37 and 39.19±5.36, p<0.001). The uterocervical angle was 100.85 (85.2-147) in preterm and 88 (70-131) degrees in terms that were statistically significant (p<0.001). Furthermore, the uterocervical angle was wider [126 (100.7-147) and 98 (85.2-114), p<0.001] in the early preterm group. When the groups with and without postpartum bleeding were compared, no significant difference was detected in terms of uterocervical angle [96.5 (71-131) and 88 (70-147), p=0.164]. Additionally, the uterocervical angle was wider in the successful induction group (p<0.001). An a uterocervical angle >85 degrees predicted preterm delivery with 100% sensitivity and 45.54% specificity [area under the curve (AUC)=0.743, p<0.001]. When the cervical length and uterocervical angle were evaluated together to predict preterm delivery, no significant difference was found (p=0.086). An a uterocervical angle >88 degrees predicted induction success with 84.78% sensitivity and 79.75% specificity (AUC=0.887, p<0.001).Conclusion:Our study revealed that the uterocervical angle can be a useful marker in predicting preterm labor and induction success, although it does not predict postpartum hemorrhage.

Fetal Fibronectin and Cervical Length as Predictors of Spontaneous Onset of Labour and Delivery in Term Pregnancies.

(1) Objective: This study aimed to determine whether qualitative fetal fibronectin and transvaginal sonographic measurement of cervical length are effective in predicting delivery in term pregnancies within 5 days of the test. (2) Methods: We examined 268 women with singleton pregnancies presenting themselves at 37+0–40+4 weeks (median 38 weeks + 1 day) of gestation with irregular and painful uterine contractions, intact membranes and cervical dilatation less than 2 cm. All women were admitted to hospital up to 72 h after birth. On admission, a qualitative fetal fibronectin test was performed in cervicovaginal secretions and transvaginal sonographic measurement of cervical length was carried out. The primary outcome measure was delivery within 5 days of presentation. RESULTS: Among the women who delivered within 5 days after admission, 65.2% had positive fFN assessment, 43.5% had cervical length below 26 mm, 52.2% had the age > 32.5 years, 34.8% were nulliparous and 56.5% had gestational age ≥ 275 days. Logistic regression analysis demonstrated that significant contributors to the prediction of delivery within 5 days were fibronectin positivity, cervical length ≤ 26 mm, maternal age > 32.5 years and gestational age ≥ 275 days, with no significant contribution from parity. (3) Conclusions: Qualitative fetal fibronectin test and transvaginal cervical length measurement in term pregnancies are useful tests for predicting spontaneous onset of labour within 5 days. It helps women and healthcare providers to determine the optimum time for hospital admission.

Comparison of transvaginal sonographic cervical length measurement and Bishop score for predicting labour induction outcomes.

Induction of labour (IOL) is of increasing prevalence worldwide and reliable prediction of its successful outcome is important. Traditional clinical methods for predicting successful IOL outcomes have been supplemented with newer technologies. The aim of this study was to compare transvaginal sonographic (TVS) cervical length measurement with Bishop score in predicting labour induction outcomes. This study included pregnant women with term pregnancy, indication for IOL and unfavourable cervix (Bishop score >6) who had TVS performed prior to IOL. Exclusion critetia were regular contractions, ruptured membranes, non-cephalic presentation, uterine scar and pregnancy complications potentially influencing study outcomes. Outcomes measured were successful IOL defined as achievement of active phase of labour and vaginal delivery. Receiver operating characteristic (ROC) curves were used to determine diagnostic accuracy and sensitivity, specificity, positive and negative predictive values. Statistical significance was defined as p<0.05. Among 112 studied participants, IOL was successful in 101 (90.2%) pregnant women. AUC for Bishop score >2 was 0.831 (95% CI, 0.744-0.917, p<0.001) and for cervical length <30mm 0.679 (95% CI 0.514-0.844, p<0.052). A total of 81 (72.3%) pregnant women delivered vaginally; AUC for Bishop score >2 was 0.754 (95% CI 0.648-0.861, p<0.001) and for cervical length <30mm 0.602 (95% CI 0.484-0.720, p=0.092) which was the only insignificant predictor. Bishop score >2 is a better predictor for both successful IOL and vaginal delivery among induced women with term pregnancy and unfavourable cervix compared to cervical length <30mm.

Transvaginal sonographic assessment of the cervix for prediction of successful induction of labor in nulliparous women

Abstract Background Induction of labor is commonly performed in obstetric practice. Many methods have been suggested as good predictors of the outcome of labor induction, yet none of them is satisfactory enough. Objective To assess cervical length and uterocervical angle measured by transvaginal ultrasound as predictors of successful induction of labor. Methodology Prospective cohort study was conducted in a university-affiliated hospital over 150 nulliparous women undergoing induction of labor, in the period between May 2018 and August 2019. Transvaginal sonographic measurement of cervical length and uterocervical angle was done before induction of labor by prostaglandins. The patients were followed up till delivery and the outcome was recorded. Results The best cut-off value of cervical length for prediction of success of labor induction was 32.3 mm with 60% sensitivity and 56% specificity and the best cutoff value of uterocervical angle was 110.2 degrees with 87% sensitivity and 93% specificity. The cervical length showed a significant negative correlation while the uterocervical angle showed a significant positive correlation with the success of labor induction. Conclusion Cervical length and uterocervical angle are good predictors of successful labor induction.

VP45.04: Sonographic cervical length measurement to predict the success of labour induction in nulliparas

VP45.04: Sonographic cervical length measurement to predict the success of labour induction in nulliparas

The association between sonographic cervical length components and preterm birth in women with ultrasound- or exam-indicated cerclage

Objective To evaluate which parameters of a sonographic cervical length measurement are associated with preterm birth in women with ultrasound- or exam-indicated cerclage. Methods This was a retrospective cohort study of women with singleton pregnancies who underwent ultrasound- or exam-indicated Shirodkar cerclage by a single maternal–fetal medicine practice between 2011 and 2019. All patients underwent sonographic cervical length measurement 2–3 weeks after cerclage placement, and then every 2–4 weeks up to 32 weeks. The images from the first and second post-cerclage cervical lengths were reviewed. Total cervical length, upper cervical length (from the internal cervical os to the cerclage), and lower cervical length (from the cerclage to the external os) were measured. The primary outcome for this study was gestational age at delivery. Results A total of 114 women with cerclage were included (85 (74.6%) ultrasound-indicated and 29 (25.4%) exam-indicated). The first and second total cervical lengths correlated with gestational age at delivery (r = 0.26, p=.005; r = 0.33, p<.001, respectively), and the change from first to second was inversely correlated with gestational age at delivery (r = −0.20, p=.032). The first and second upper cervical lengths also correlated with gestational age at delivery (r = 0.22, p = .019; r = 0.33, p<.001, respectively), and the change from first to second upper cervical length was inversely correlated with gestational age at delivery (r= −0.20, r = 0.029). Neither the first nor the second lower cervical lengths were significantly associated with gestational age at delivery. On regression analysis, total cervical length and upper cervical length were not independently associated with gestational age at delivery (p = .108 and p=.806, respectively, for the first scan; p = .153 and p=.166, respectively, for the second scan). Conclusions Postcerclage total cervical length and upper cervical length are both associated with gestational age at delivery and risk of preterm birth, but not independently. After ultrasound- or exam-indicated cerclage, sonographic monitoring of either the total cervical length or the upper cervical length might be predictive of gestational age at delivery and the risk of preterm birth.

Sonographic measurement of cervical length and head perineum distance before labor to predict time of delivery

Objectives This was an observational study on cervical length and head perineum distance and the prediction of time of delivery. One-hundred and twenty-five nulliparous women with uncomplicated, term, singleton pregnancy were recruited when they presented to the labor ward with show or infrequent painful uterine contractions (less than three contractions in ten minutes on a 30 min cardiotocogram). Apart from digital vaginal examination to assess cervical length and dilatation, sonographic cervical length and head perineum distance were measured by two-dimensional ultrasound. We compared women who delivered within 72 h of presentation of labor symptoms, with women who did not. After excluding ten women whose labor was induced and delivered within 72 h of presentation, one hundred and fifteen women were included for final data analysis. Main findings Forty-nine women (42.6%) delivered while sixty-six women (57.4%) remained undelivered at 72 h of presentation of symptoms of labor. There was no statistically significant difference between the two groups on age, presence of show, contractions, fetal head station and presentation and mode of delivery. For the group who had delivered within 72 h of presentation of labor symptoms, the mean sonographic cervical length was 1.87 cm ± 0.62 cm, while the head perineum distance was 6.01 cm ± 1.15 cm. For the other group, the mean sonographic cervical length was 2.10 cm ± 0.83 cm; head perineum distance was 6.03 cm ± 1.18 cm. There was no statistically significant difference between the groups for both sonographic cervical length (p = .90); and head perineum distance (p = .08). We also compared the cervical length measured by digital vaginal examination versus sonography. The median sonographic measurements were 1.47 cm, 2.11 cm and 2.79 cm at “1 cm,” “2 cm” and “3 cm” digital vaginal measurement, respectively. However, there was extensive overlap between digitally and sonographically measured cervical length. Prediction accuracy of cervical length and head perineum distance was poor. The area under curve (AUC) of receiver operating characteristic (ROC) curve were 0.433 for sonographic cervical length and 0.501 for HPD. Conclusion Transperineal sonographical assessment of cervical length and head perineum distance before labor was not useful in predicting the time of delivery. However, it can be explored as an alternative assessment method when digital vaginal examination is not preferred.

ASSESSMENT OF CERVICAL LENGTH, SHAPE AND CONSISTENCY BETWEEN 18-24 WEEKS GESTATIONAL AGE BY TRANSVAGINAL ULTRASOUND FOR PREDICTION OF PRETERM LABOR

Background: Preterm labor is the presence of uterine contractions of sufficient frequency and intensity to affect progressive effacement and dilation of the cervix prior to term gestation. Shortening and funneling of the cervix was first described to be associated with the diagnosis of cervical incompetence, Transvaginal sonographic measurement of cervical length could be used to predict a risk for preterm delivery for a significant proportion of preterm births. Cervical length is measured by transvaginal ultrasound from internal os to external os while the urinary bladder is empty. Objective: To determine the value of measurement of cervical parameters by transvaginal ultrasound between 18 and 24 weeks' gestation in the prediction of spontaneous preterm delivery. Patients and Methods: The study was carried out at Bab EL-Sha'aria University Hospital between 1/10/2018 and 31/12/2019 on 200 primigravida women with single pregnancy and intact membranes. Women with scarred uterus, women with chronic medical diseases or obstetric problems, women who underwent cerclage and fetal anomalies were excluded from the study. For all participants, transvaginal ultrasound was done between 18 and 24 weeks' gestation for measurement of cervical length, shape and consistency. Results: Infant means weight at delivery was 1589 g with SD 215 in preterm delivery, while Infant mean weight at delivery was 3024 g with SD 200 which was significant. 33.3% of preterm birth delivered vaginally, while 66.7% delivered by C.S. 62.6% of full term delivery delivered vaginally, while 37.4% delivered by C.S. No statistically significant difference was found regarding mode of delivery. Cervical length was significant in prediction of preterm labor with sensitivity 88.9%, specificity 91.2%, PPV 50.0% and NPV 98.8 %. Cervical consistency index was significant in prediction of preterm labor with sensitivity 88.9%, Specificity 93.4%, PPV 57.1% and NPV 98.8 %. Funneling was present in 33.3% of preterm delivery, and 4.4% of full term delivery which was significant. Measurement of cervical length, shape and consistency was a reliable method for prediction of preterm labor. Conclusion: Measurement of cervical length, shape and consistency by transvaginal ultrasound between 18 and 24 weeks' gestation was a reliable method for prediction of preterm labor.

ASSESSMENT OF CERVICAL LENGTH, SHAPE AND CONSISTENCY BETWEEN 18-24 WEEKS GESTATIONAL AGE BY TRANSVAGINAL ULTRASOUND FOR PREDICTION OF PRETERM LABOR

Background: Preterm labor is the presence of uterine contractions of sufficient frequency and intensity to affect progressive effacement and dilation of the cervix prior to term gestation. Shortening and funneling of the cervix was first described to be associated with the diagnosis of cervical incompetence, Transvaginal sonographic measurement of cervical length could be used to predict a risk for preterm delivery for a significant proportion of preterm births. Cervical length is measured by transvaginal ultrasound from internal os to external os while the urinary bladder is empty. Objective: To determine the value of measurement of cervical parameters by transvaginal ultrasound between 18 and 24 weeks' gestation in the prediction of spontaneous preterm delivery. Patients and Methods: The study was carried out at Bab EL-Sha'aria University Hospital between 1/10/2018 and 31/12/2019 on 200 primigravida women with single pregnancy and intact membranes. Women with scarred uterus, women with chronic medical diseases or obstetric problems, women who underwent cerclage and fetal anomalies were excluded from the study. For all participants, transvaginal ultrasound was done between 18 and 24 weeks' gestation for measurement of cervical length, shape and consistency. Results: Infant means weight at delivery was 1589 g with SD 215 in preterm delivery, while Infant mean weight at delivery was 3024 g with SD 200 which was significant. 33.3% of preterm birth delivered vaginally, while 66.7% delivered by C.S. 62.6% of full term delivery delivered vaginally, while 37.4% delivered by C.S. No statistically significant difference was found regarding mode of delivery. Cervical length was significant in prediction of preterm labor with sensitivity 88.9%, specificity 91.2%, PPV 50.0% and NPV 98.8 %. Cervical consistency index was significant in prediction of preterm labor with sensitivity 88.9%, Specificity 93.4%, PPV 57.1% and NPV 98.8 %. Funneling was present in 33.3% of preterm delivery, and 4.4% of full term delivery which was significant. Measurement of cervical length, shape and consistency was a reliable method for prediction of preterm labor. Conclusion: Measurement of cervical length, shape and consistency by transvaginal ultrasound between 18 and 24 weeks' gestation was a reliable method for prediction of preterm labor.

It is about time. The advantage of transabdominal cervical length screening

Purpose Sonographic cervical length (CL) measurement has become a standard practice for identifying women at increased risk for preterm birth. We aimed to assess the time needed for CL measurement during fetal anatomy scan using either transabdominal or transvaginal ultrasound, and to provide a predictive value of the transabdominal CL measurements for reassuring transvaginal CL measurements of more than 25 mm. Methods In a prospective study we measured CL transabdominally, and transvaginally in all the anatomy scans performed at 18–25 weeks’ gestation, from January 2017 until January 2018. CL and the duration of the examination were compared between the two approaches. Adjustments were made for, body mass index, previous cesarean sections and parity. Results Four hundred sixty-eight patients participated in the study. The time needed for the transabdominal CL measurement was significantly lower compare with the transvaginal CL measurement (0.46 ± 0.3 min versus 6.9 ± 1.38 min, p < 0.001). The CL measured transabdominally was significantly shorter than the CL measured transvaginally (36.7 ± 6.7 mm versus 41.9 ± 7.3 mm, respectively p < 0.001). All women with transabdominal CL measurements above 36 mm (64.2% of patients) had a transvaginal CL of more than 25 mm. Conclusion Transvaginal measurement of CL is a time-consuming procedure that prolong fetal anomaly scan by 25%. Transabdominal CL measurement of 36 mm is reassuring CL above 25 mm. Transabdominal ultrasound should be used as an initial tool for CL screening. Transvaginal measurements of CL should be reserved for high-risk women, for women with difficulties in demonstrating the cervix abdominally, and for women with transabdominal measurements of less than 36 mm.

The Effect of Ultrasound-Measured Preinduction Cervical Length on Delivery Outcome in a Low-Resource Setting

Background Induction of labour is not without risk, and it calls for a method that will be sensitive enough to predict successful labour induction. Aim This study aims to evaluate the role of transvaginal ultrasonographic cervical length measurement at term in the prediction of successful induction of labour (IOL). Materials and Methods This prospective study was carried out in the Department of Obstetrics and Gynaecology of Federal Teaching Hospital Abakaliki between 1st of July and 30th of November 2015. Preinduction Bishop score and cervical length were assessed before induction of labour. Intracervical, cervical, extraamniotic Foley catheter was used to improve the Bishop score. The data were analyzed using the IBM SPSS Statistics 20. Results The mean maternal age of the study group was 30.68 ± 6.38 years with a range of 19–43 years. The mean gestational age and parity were 39.57 ± 1.49 and 1.85 ± 0.63, respectively. All the women studied had successful induction of labour with mean induction delivery time of 8.1 ± 3.0 hours and mean duration of labour of 7.4 ± 2.9 hours. Preinduction cervical length is a good predictor of a short duration of labour (P = 0.001). Parturient with a preinduction cervical length of less than 3 cm was likely to have labour lasting less than 6 hours (RR = 4.20 (95% CI 1.85–9.529). Conclusion Transvaginal sonographic measurement of cervical length provides a useful prediction of the likelihood of duration of labour following the induction of labour. It is recommended that IOL should be considered and success anticipated in a parturient with a cervical length less than 3 cm.

Transvaginal Sonographic Assessment of the Cervix for Prediction of Successful Induction of Labor in Nulliparous Women

Background: Induction of labor is commonly performed in obstetric practice. Many methods have been suggested as good predictors of the outcome of labor induction, yet none of them is satisfactory enough. Our study aims to assess cervical length and uterocervical angle measured by transvaginal ultrasound as predictors of successful induction of labor. Methods: Prospective cohort study conducted in Ain Shams University Maternity hospital over 150 nulliparous women undergoing induction of labor, in the period between May 2018 and August 2019. Transvaginal sonographic measurement of cervical length and uterocervical angle was done before induction of labor by prostaglandins. The patients were followed up till delivery and the outcome was recorded. Results: The best cut-off value of cervical length for prediction of success of labor induction was 32.3 mm with 60% sensitivity and 56% specificity and the best cut-off value of uterocervical angle was 110.2 degrees with 87% sensitivity and 93% specificity. The cervical length showed a significant negative correlation while the uterocervical angle showed a significant positive correlation with the success of labor induction. Conclusion: Cervical length and uterocervical angle are good predictors of successful labor induction.

The predictive value of cervical shear wave elastography in the outcome of labor induction.

IntroductionBishop score, the traditional method to assess cervical condition, is not a promising predictive tool of the outcome of labor induction. As an objective assessment tool, many cervical ultrasound measurements have been proposed to represent the individual components of the Bishop score, but none of them can measure the cervical stiffness. Cervical shear wave elastography is a novel tool to assess the cervical stiffness quantitatively.Material and methodsA total of 475 women who required labor induction were studied prospectively. Prior to routine digital assessment of the Bishop score, transvaginal sonographic measurement of cervical length, posterior cervical angle, angle of progression and shear wave elastography was performed. Shear wave elastography measurement was made at the inner, middle and outer regions of the cervix to assess homogeneity. Association of labor induction outcomes including the overall cesarean section and subgroups of cesarean section for failure to enter active phase, with cervical sonographic parameters and the Bishop score, were assessed using multivariate regression analyses. The predictive accuracy of the outcomes using models based on ultrasound measurement and the Bishop score was compared using the area under the receiver‐operating characteristics curves.ResultsAmong 475 women, 82 (17.3%) required cesarean section. Shear wave elasticity was significantly higher in the inner cervical region than in other regions, indicating a greater stiffness (P < 0.001). Both inner cervical shear wave elasticity and cervical length were independent predictors of overall cesarean section (respective adjusted odds ratio [95% CI] 1.338 [1.001‐1.598] and 1.717 [1.077‐1.663]) and cesarean section for failure to enter active phase (respective adjusted odds ratio [95% CI] 1.689 [1.234‐2.311] and 2.556 [1.462‐4.467]), after adjusting for other covariates. Outcome prediction models using inner cervical shear wave elasticity and cervical length, had increased area under curve compared with models using the Bishop score (0.888 vs 0.819, P = 0.009).ConclusionsThe cervix is not a homogenous structure, with the inner cervix having the highest stiffness, which is an independent predictor of overall cesarean section, and specifically for those indicated because of failure to enter active phase. Models based on shear wave elastography and cervical length had higher predictive accuracy than models based on the Bishop score.

Prediction of time of delivery using cervical length measurement in women with threatened preterm labor

Objective To evaluate the use of transvaginal (TV) sonographic cervical length (CL) measurement alone in predicting time of delivery in women who present in threatened preterm labor. Methods A retrospective cohort study at Royal Brisbane and Women’s Hospital of all women who presented between 22 weeks and 0 days and 35 weeks and six-day gestation in threatened preterm labor and were admitted for ongoing management including a TV sonographic CL measure. The accuracy of CL for predicting time of delivery was compared between women with a short cervix (CL < 25 mm) and those with a normal cervix (CL ≥25 mm). The predictive accuracy of CL for spontaneous preterm delivery was analyzed with different outcome-specific thresholds. Results One hundred and forty-six women with threatened preterm labor met the inclusion criteria; of which 74 (50.7%) had a short cervix and 72 (49.3%) had a normal cervix. The group with short cervix were more likely to deliver prematurely before 37-week gestation, as well as a shorter time interval between initial presentation and delivery and delivery within 14 days from presentation (p = .0002, p = .0001, and p = .0001, respectively). Similarly, with respect to the area under the receiver operator characteristic curves, CL measurement was found to be significant for time of delivery before or after 37 weeks (p < .0001), preterm delivery before 34 (p = .0003) and 31 (p < .0001) weeks; and preterm delivery within 14 days from presentation (p < .0001). Cervical length measurement has a high negative predictive value ranging from 94.9 to 97.1% depending on the different CL threshold used. Conclusions Cervical length measurement at the time of presentation was significantly associated with the risk of preterm delivery in women presenting with threatened preterm labor and a short cervix. Cervical length measurement was also helpful in predicting time of delivery within 14 days from presentation. The negative predictive value and predictive accuracy of CL as a single measure were of significance.