Transvaginal Ultrasound Measurement Of Cervical Length Research Articles

Comparison of trans-vaginal ultrasound cervical length measurement and Bishop score in predicting successful labour induction in term pregnancies at Ahmadu Bello University Teaching Hospital Zaria

The goal of induction of labour (IOL) is to achieve successful vaginal delivery and reduce caesarean section (CS). The gold standard method for assessing cervical status has been the use of the Bishop score (BS) which is not flawless leading to unnecessary intervention. Trans-vaginal ultrasound cervical length (CL) measurement has been compared with BS in predicting successful IOL. The objective of this study was to compare CL and BS in predicting successful IOL at Ahmadu Bello University Teaching Hospital. It was a cross sectional comparative study design conducted among pregnant women at 37-42 weeks of gestation slated for IOL between November 2017 to November 2018. Eighty-seven (87) women were recruited as participants. Each participant, had a trans-vaginal ultrasound (TVS) CL measured and each was followed by a digital cervical assessment using BS. Relevant data obtained was analysed using SPSS version 23. The significance level was considered at P< 0.05 IOL was successful in 66.2% (47) of the participants, while 15% (13) had CS. The receiver operating characteristic curve (ROC) demonstrated a better performance of the BS (AUC= 0.556, P= 0.433, CI= 0.426-0.673, PPV=52.8%) in predicting successful IOL than the TVS-CL measurement (AUC= 0.446, P=0.391, CI= 0.317-0.574) PPV=60.2%). Results further showed that the best cut off values for favourability for IOL for TVS-CL and BS were ≤2.5 cm and ≥5 respectively. The most important component of the BS predictive of successful IOL was cervical dilatation (OR= 0.603, P=0.011). TVS-CL did not demonstrate a diagnostic accuracy in predicting successful IOL in term pregnancies compared to BS.

Changes of uterocervical angle and cervical length in early and mid-pregnancy and their value in predicting spontaneous preterm birth.

Objective: To explore the feasibility of transvaginal ultrasound measurement of uterocervical angle (UCA) and cervical length (CL) in early and mid-pregnancy and evaluate their combined prediction of spontaneous preterm birth (sPTB) in singleton pregnancies. Patients and Methods: This retrospective study comprised 274 pregnant women who underwent transvaginal ultrasound measurement of CL in mid-pregnancy (15-23+6weeks); in 75 among them, CL also had been measured in early-pregnancy (<14 weeks). These 274 pregnant women were further divided into a preterm group (n = 149, <37weeks gestation) and a control group (n = 125, >37weeks gestation) according to delivery before or after 37weeks, respectively. In the preterm group, 35 patients delivered before 34weeks and the remaining 114 delivered between 34 and 37weeks. Results: The optimal threshold of CL to predict preterm birth risk in women with <37weeks gestation was 3.38cm, and the optimal threshold of the UCA to predict preterm birth risk in the same group of women was 96°. The optimal threshold of CL to predict preterm birth risk in women with <34weeks gestation was 2.54cm, while that of the UCA in the same group of patients was 106°. The area under the curve for predicting preterm birth by combining the UCA and CL measurements was greater than that by using the UCA or CL alone (p < 0.01). The sensitivity and specificity for predicting preterm birth at <34 weeks gestation was 71.7% and 86.4%, respectively; and the sensitivity and specificity for predicting preterm birth at <37weeks gestation was 87.6% and 80.6%, respectively. The difference between the two groups in CL and UCA were not significant in early pregnancy (p > 0.01), but only in mid-pregnancy (p < 0.01). There was a negative correlation between UCA and gestational week at delivery (r = -0.361, p < 0.001) and a positive correlation between CL and gestational week at delivery (r = 0.346, p < 0.001) in mid-pregnancy. The proportion of deliveries at <34 weeks was highest when the UCA was >105°, and the proportion of deliveries between 35 and 37weeks was highest when the UCA was between 95° and 105°. The proportion of deliveries at <34weeks was highest when the CL was <2.5cm. Conclusion: The combination of UCA and CL has a better ability to predict preterm birth than either measurement alone. A more obtuse UCA or a shorter CL is associated with an earlier spontaneous preterm birth. The UCA increases from early to mid-pregnancy, while the CL decreases from early to mid-pregnancy.

Comparing Transvaginal Ultrasound Measurements of Cervical Length to Bishop Score in Predicting Cesarean Section Following Induction of Labor: A Prospective Observational Study.

Bishop score (BS) has been used to see the favorability of the cervix for induction of labor (IOL), but it has limitations in today's diverse patient population.We aimed to assess the predictive value of transvaginal ultrasound (TVUS) measurements of cervical length (CL) compared to BS in determining the likelihood of cesarean section (CS) following IOL. A prospective observational study was conducted on 120 women requiring IOL in a tertiary care hospital in central India. The inclusion criteria of the study were antenatal women more than 18 years of age, in need of IOL, having a singleton pregnancy with a gestational age of > 37 weeks as determined from the date of the last menstrual period and confirmed by sonographic measurements in the first trimester, presenting with a cephalic presentation, and having intact fetal membranes. Women with prior uterine scars and those unwilling to IOL were excluded from the study. TVUS was done just before induction. Statistical analyses were done to compare the predictive abilities of CL and BS for CS. The mean age and gestation period were 25.96 years and 39 weeks 3 days, respectively. The majority of the study population comprised multigravida (69, 57.5%), followed by primigravida (47, 39.2%), and grand multigravida (≥ G5) (4, 3.3%). Post-maturity (34, 28.3%), preeclampsia (21, 17.5%), and intrahepatic cholestasis of pregnancy (17, 14.2%) were common indications for induction. The overall CS rate was 35.8% (43/120). Women with CS had lower BS (3.60 vs. 4.70,P= 0.010) and higher CL (31.5 mm vs. 23.4 mm, P < 0.001). CL exhibited an area under the curve (AUC) of 0.857, outperforming BS (AUC = 0.643) in predicting CS. Using a CL cutoff of 26.5 mm yielded sensitivity (79.1%), specificity (81.8%), and overall accuracy (80.8%). TVUS measurement of CL (>26.5 mm) demonstrated superior predictive ability for CS following labor induction compared to BS (≤5). This study highlights the potential of CL measurement as an objective and reliable tool for optimizing decision-making in labor induction.

Utility of follow-up cervical length screening in low-risk women with a cervical length of 26 to 29 mm

In women with a previous preterm birth, a protocol for serial cervical length screening has been studied and recommended for the identification and treatment of a short cervix. Cervical length screening along with vaginal progesterone has been suggested for low-risk women with singleton pregnancies to treat a short cervix and reduce preterm birth. However, specific protocols for single vs serial ultrasound measuring cervical length in this population are not established. Cost-effectiveness of universal cervical length screening depends on the cost of screening; follow-up of borderline measurements can contribute to increased costs with uncertain benefit. This study aimed to determine the utility of follow-up cervical length screening in otherwise low-risk women with singleton pregnancies with a midtrimester cervical length measurement of 26 to 29 mm through the assessment of the rate of short cervix (≤25 mm) on follow-up ultrasound and subsequent delivery outcomes. This was a 2-year retrospective cohort study at a single urban institution of women with singleton pregnancies with no previous spontaneous preterm birth and an initial transvaginal ultrasound cervical length measurement of 26 to 29 mm identified during universal cervical length screening at time of anatomy ultrasound (18 0/7 to 22 6/7 weeks' gestation). The primary outcome was the rate of short cervix (defined as ≤25 mm on transvaginal ultrasound) on follow-up ultrasound at <24 weeks' gestation. Secondary outcomes included the rate of spontaneous preterm birth (<37 and <34 weeks' gestation). During the study period, there were 2801 women with singleton pregnancies at 18 0/7 to 22 6/7 weeks' gestation with transvaginal ultrasound cervical length screening at time of anatomy scan. Among those women, 201 had a cervical length of 26 of 29 mm, and 184 (7%) had no previous spontaneous preterm birth and were included in the study. Furthermore, 144 women (78%) had a follow-up cervical length completed before 24 weeks' gestation. The mean follow-up interval was 1.5±0.6 weeks. Overall, the percentage of short cervix (≤25 mm) on follow-up was 15% (n=21). Baseline characteristics were similar, but the initial cervical length measurement was shorter in women who subsequently developed a short cervix (26.7±0.8 vs 27.8±1.0; P<.01). Delivery outcomes were available for 126 patients. The rate of spontaneous preterm birth at <37 weeks' gestation in women with an initial cervical length 26 to 29 mm and subsequent short cervix was significantly higher than the rate of spontaneous preterm birth in a historical cohort of low risk women with an initial cervical length >25 mm (16% vs 3%; P=.03). The rate of spontaneous preterm birth at <34 weeks' gestation in women with a subsequent short cervix was 11% (2 of 19). Here, approximately 15% of low-risk women with singleton pregnancies with a midtrimester cervical length measurement of 26 to 29 mm will experience cervical shortening of ≤25 mm before 24 weeks' gestation. Compared to women with singleton pregnancies without a history of preterm birth, the rate of spontaneous preterm birth (16%) in women with an initial cervical length of 26 to 29 mm and a subsequent cervical shortening of ≤25 mm is significantly higher. A total of 111 follow-up ultrasounds measuring cervical length would be required to prevent 1 early preterm birth at <34 weeks' gestation.

Development and validation of predictive models for QUiPP App v.2: tool for predicting preterm birth in asymptomatic high-risk women.

Accurate mid-pregnancy prediction of spontaneous preterm birth (sPTB) is essential to ensure appropriate surveillance of high-risk women. Advancing the QUiPP App prototype, QUiPP App v.2 aimed to provide individualized risk of delivery based on cervical length (CL), quantitative fetal fibronectin (qfFN) or both tests combined, taking into account further risk factors, such as multiple pregnancy. Here we report development of the QUiPP App v.2 predictive models for use in asymptomatic high-risk women, and validation using a distinct dataset in order to confirm the accuracy and transportability of the QUiPP App, overall and within specific clinically relevant time frames. This was a prospective secondary analysis of data of asymptomatic women at high risk of sPTB recruited in 13 UK preterm birth clinics. Women were offered longitudinal qfFN testing every 2-4 weeks and/or transvaginal ultrasound CL measurement between 18 + 0 and 36 + 6 weeks' gestation. A total of 1803 women (3878 visits) were included in the training set and 904 women (1400 visits) in the validation set. Prediction models were created based on the training set for use in three groups: patients with risk factors for sPTB and CL measurement alone, with risk factors for sPTB and qfFN measurement alone, and those with risk factors for sPTB and both CL and qfFN measurements. Survival analysis was used to identify the significant predictors of sPTB, and parametric structures for survival models were compared and the best selected. The estimated overall probability of delivery before six clinically important time points (< 30, < 34 and < 37 weeks' gestation and within 1, 2 and 4 weeks after testing) was calculated for each woman and analyzed as a predictive test for the actual occurrence of each event. This allowed receiver-operating-characteristics curves to be plotted, and areas under the curve (AUC) to be calculated. Calibration was performed to measure the agreement between expected and observed outcomes. All three algorithms demonstrated high accuracy for the prediction of sPTB at < 30, < 34 and < 37 weeks' gestation and within 1, 2 and 4 weeks of testing, with AUCs between 0.75 and 0.90 for the use of qfFN and CL combined, between 0.68 and 0.90 for qfFN alone, and between 0.71 and 0.87 for CL alone. The differences between the three algorithms were not statistically significant. Calibration confirmed no significant differences between expected and observed rates of sPTB within 4 weeks and a slight overestimation of risk with the use of CL measurement between 22 + 0 and 25 + 6 weeks' gestation. The QUiPP App v.2 is a highly accurate prediction tool for sPTB that is based on a unique combination of biomarkers, symptoms and statistical algorithms. It can be used reliably in the context of communicating to patients the risk of sPTB. Whilst further work is required to determine its role in identifying women requiring prophylactic interventions, it is a reliable and convenient screening tool for planning follow-up or hospitalization for high-risk women. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Effects of antibiotic therapy in women with the amniotic fluid “sludge” at 15–24 weeks of gestation on pregnancy outcomes

Objective: The aim of this prospective study was to assess the efficacy of antibiotic therapy for the prevention of adverse pregnancy outcomes in women with the amniotic fluid “sludge” at 15–24 weeks of gestation.Methods: 245 women underwent transvaginal ultrasound cervical length measurement at 15–24 weeks of pregnancy and 29 out of them with amniotic fluid “sludge” were included in the study. Eight women with the “sludge” had cervical length >25 mm (Group I), seven—an asymptomatic short cervix (Group IIa) and 14 women with a short cervix had symptoms like low abdominal pain, back pain, and menstrual-like cramps (Group IIb). All participants received intravenous, oral and/or vaginal antibiotic therapy. Participants in Group IIa were additionally given vaginal progesterone (VP), and in Group IIb—VP and indomethacin. Placentas from women with preterm birth (PTB) underwent histological examination.Results: The amniotic fluid “sludge” detected at an ultrasound scan between 15–24 weeks of gestation was associated with long-term maternal infections, histological chorioamnionitis, and was viewed as a marker of intra-amniotic infection. Absence of intravenous antibiotic therapy during midtrimester of pregnancy in these women was associated with neonatal infection with intrauterine onset in 61.1%, postpartum endometritis in 23.1%, and rate of PTB 46.2%. Intravenous antibiotic therapy eliminated sonographic presence of the sludge and resulted in prevented of neonatal and postpartum infections, prevented the risk of PTB in women with the cervical length >25 mm, in those with an asymptomatic short cervix receiving VP, and in 70% of symptomatic women with a short cervix, who received them in combination VP/indomethacin. For those women whose approach was not fully beneficial, it allowed to delay delivery in 11–17 weeks.Conclusions: Although we found that intravenous antibiotic therapy at 15–24 weeks of gestation in women with amniotic fluid “sludge” can protect from infection-related complications and demonstrated high beneficial effects of adding antibiotics to anti-inflammatory drug (indomethacin) and/or VP in women with a short cervix, further larger studies are needed.

Vaginal alpha-lipoic acid shows an anti-inflammatory effect on the cervix, preventing its shortening after primary tocolysis. A pilot, randomized, placebo-controlled study

Introduction: Inflammation might be an important underlying cause of preterm birth. Our aim is to explore whether vaginal administration α-lipoic acid reduces cervical inflammation and shortening after primary tocolysis.Materials and methods: Singleton pregnancies between 24–30 weeks remaining undelivered after hospitalization for preterm labor were randomly allocated to placebo (20 women, 15 analyzed) or vaginal ALA 400 mg (active ingredient 10 mg) daily (20 women, 17 analyzed) for 30 days. A cervical swab to quantify pro-inflammatory (IL1, IL2, IL6, IL8, TNFα) and anti-inflammatory (IL4, IL10) cytokines as well as transvaginal ultrasound cervical length measurement (CL) were performed before and after treatment.Results: The % changes of pro-inflammatory cytokines do not differ between treatment groups, while IL4 significantly increases by vaginal ALA in comparison to placebo (118.0 ± 364.3% versus 29.9 ± 103.5%, p = 0.012). Combined anti-inflammatory cytokines show same trend (292.5 ± 208.5% versus 64.5 ± 107.4, p = 0.03). CL remains similar in vaginal ALA group (from 23.1 ± 6.6 to 20.80 ± 7.9 mm), while it significantly decreased in placebo group (from 20.4 ± 6.5 to 13.8 ± 7.5 mm, p < 0.001 versus Baseline; p = 0.003 versus vaginal ALA).Conclusion: Vaginal ALA significantly stimulates anti-inflammatory ILs in the cervix of undelivered women after a preterm labor episode. This effect is associated with a stabilization of the CL.

An Educational Intervention to Improve Physician Confidence and Knowledge About Transvaginal Sonographic Cervical Assessment in Obstetric Patients

Local Mentor: David Forstein, DO APGO Advisors: Jody Steinauer, MD, MAS, and Sonya Erickson, MD PURPOSE: To evaluate the effect of an educational intervention about transvaginal sonographic cervical length (CL) measurement on obstetrics and gynecology residents' confidence and knowledge. BACKGROUND: Preterm labor admissions are costly. Transvaginal ultrasound measurement of CL has a high negative predictive value for preterm delivery, and can help triage patients with symptoms. Education about transvaginal CL measurement may increase use of this screening tool when triaging patients with preterm labor symptoms. METHODS: This was a before and after study of OB/Gyn residents at a single institution. The intervention consisted of an educational module adapted from a preexisting module from AIUM. Nine pre- and post-test questions evaluated knowledge. Residents were asked about their confidence with each answer and in doing CL measurements. Chi-squared tests were used to compare proportions and ordinal data, and Wilcoxon rank sum test the proportion of correct answers. RESULTS: Twenty-one residents participated. The proportion of residents answering 89% or more of the questions correctly increased from 5% before to 81% (P&lt;.01). The level of confidence about answers to knowledge-based questions about the technique increased significantly, (P&lt;.01) however confidence in doing CL measurement did not change, with 52% of residents saying they were not confident before and 38% after the intervention (P=.4). DISCUSSION: An educational module can increase knowledge about the utility and performance of cervical length measurement, but does not change confidence in doing the measurement. Future efforts should include curricula to teach the actual measurement.

Evaluation of additive effect of quantitative fetal fibronectin to cervical length for prediction of spontaneous preterm birth among asymptomatic low-risk women.

Our objective was to evaluate the possible additive effect of quantitative fetal fibronectin to transvaginal ultrasound cervical length measurement between 18(0/7) and 23(6/7) weeks for prediction of spontaneous preterm birth at <37(0/7) weeks among asymptomatic low-risk women. A prospective observational study was performed of asymptomatic women with singleton gestations between 18(0/7) and 23(6/7) weeks and no prior spontaneous preterm birth. Women with multiple gestations, rupture of membranes, vaginal bleeding, intercourse or vaginal exam within 48h of enrollment were excluded. Physicians were blinded to the quantitative fetal fibronectin levels, but the cervical length measurements were made available. The primary outcome was spontaneous preterm birth at <37(0/7) weeks. Of the 528 asymptomatic low-risk women who were prospectively enrolled, 36 (6.82%) had spontaneous preterm birth at <37(0/7) weeks. Using the receiver-operating characteristic curve, fetal fibronectin value of ≥5ng/mL was identified as the optimal cut-off for predicting spontaneous preterm birth at <37(0/7) weeks. As compared with cervical length ≥20mm alone, with the use of cervical length ≤20mm or quantitative fetal fibronectin ≥5ng/mL as screening criteria for prediction of spontaneous preterm birth at <37(0/7) weeks; sensitivity improved from 11.11 to 61.11%, specificity decreased from 99.59 to 55.08%, positive predictive value decreased from 66.67 to 9.05%, negative predictive value marginally improved from 93.87 to 95.09% and predictive accuracy decreased from 93.56 to 55.49%. Although the sensitivity improved, other predictive statistics and predictive accuracy did not improve by the addition of mid-trimester quantitative fetal fibronectin to cervical length measurement. Therefore, addition of mid-trimester quantitative fetal fibronectin to cervical length measurement cannot be recommended at this time for prediction of spontaneous preterm birth at <37(0/7) weeks in asymptomatic low-risk women.

Assessment of a cervicometer compared to transvaginal ultrasound in identifying women with a short cervical length: a multicenter study

Preterm birth remains a major cause of neonatal morbidity and mortality worldwide. Short cervical length (CL) as measured by transvaginal ultrasound (TVU) in the second trimester represents the single most predictive risk factor for spontaneous preterm birth. Previous studies have addressed, in part, the limitations of TVU availability by utilizing a cervicometer to screen patients for short cervix, identifying those patients who may not benefit from TVU CL screening. In view of the prior studies indicating that a cervicometer measurement may have a high negative predictive value (NPV) for a sonographically short cervix, we sought to identify the ideal cervicometer threshold value in a prospective, multicenter study. The primary objective was to determine the cervicometer CL measurement threshold that provides a high NPV for the identification of patients who are highly unlikely to have a TVU CL measurement ≤20 and ≤25 mm and, therefore, may forego TVU. This prospective study, executed in 5 US centers, included 401 women ≥18 years of age who provided written informed consent to undergo CL measurement in the mid trimester. All women underwent both cervicometer- and TVU-measured CLs by individuals blinded to results of the other measurement. Both measurements were performed at 17-23 weeks' gestation (visit 1) and repeated at 24-29 weeks' gestation (visit 2). All TVU measurement images were reviewed by a central reader. Test characteristics and receiver operating characteristic curves were created to determine and confirm the optimal cervicometer CL threshold, maximizing the NPV. In all, 358 subjects were evaluable at visit 1 and 267 at visit 2. At visit 1, the average TVU CL was 38.7 ± 7.6 mm and the average cervicometer CL was 30.3 ± 8.8 mm. Similar measurements were seen at visit 2. Receiver operating characteristic curves were utilized to graphically identify a cervicometer CL threshold of 30 mm that maximized sensitivity while minimizing the false-positive rate. The 30-mm cervicometer CL threshold provided a 98-100% NPV and 0.0 negative likelihood ratio for identification of women who have a low likelihood to have a sonographic short cervix (ie, transvaginal CL ≤20 mm or ≤25 mm). The 17-23 weeks' gestation 30-mm cervicometer CL threshold has 100% sensitivity, 45-46% specificity, and 1.8 and 0.0 positive and negative likelihood ratios to predict sonographic CL ≤20 and ≤25 mm. Cervicometer CL screening successfully identifies women at low risk for short transvaginal CL. Use of a 30-mm threshold by cervicometer CL measurement confers a 98-100% NPV, with high sensitivity and moderate specificity to predict a TVU short CL. Cervicometer measurement of CL may permit almost 50% of women to avoid TVU.

Transperineal versus transvaginal ultrasound cervical length measurement and preterm labor.

The aim was to evaluate the agreement between and the reproducibility of transperineal and transvaginal ultrasound cervical length measurements performed by the duty obstetrical team in case of preterm labor. The acceptability of transperineal ultrasonography was also assessed. Pregnant patients between 25 and 34weeks of gestation with contractions and a clinically modified cervix were included. Order of ultrasonography examination (transperineal or transvaginal first) and rank of operator (resident or senior) were allocated randomly. Agreement was assessed using the intraclass correlation coefficient (ICC) and the Bland and Altman plot. The patient's discomfort and preference for either method were assessed with a questionnaire. 62 patients admitted for preterm labor between 25 and 34weeks of gestation were included. Six seniors and nine residents took part in the study. Among the 51 patients with an interpretable transperineal ultrasound scan, median cervical length measurements with the transperineal and the transvaginal technique were, respectively, 25mm (0-53) and 27mm (4-51). Concordance was good with an ICC of 0.83 [IC 95%=(0.73-0.90)]. Transperineal ultrasonography was preferred in 56.5% of cases. In case of preterm labor, cervical length measurement with transperineal ultrasonography seems reproducible and can be performed by the obstetric team on duty.

Prevention and Management of Preterm Birth

Prevention and treatment of preterm delivery is not one of the success stories of modern medicine, preterm birth constitutes the major determinant of perinatal mortality and morbidity, and the long-term results of being born too early often lead to a shorter, less healthy life and a more difficult school and professional career. Different methods have been introduced to predict the advent of preterm labour in asymptomatic women, including fetal fibronectin and transvaginal ultrasound cervical length measurement. R. Arisoy and M. Yayla present data on the evaluation of the cervix in asymptomatic singleton pregnancies; they also address the most frustrating issue: what measures to take once a short cervix has been detected. They restrict their study to singleton pregnancies; although both cervical length and fetal fibronectin are good predictors of preterm delivery in twins, no intervention has proven useful in twins: vaginal progesteron makes no difference and cerclage even worsens the outcome. Possibilities for real primary prevention are rare and include treatment of asymptomatic bacteriuria and periodontal disease. O. Huck et al. elaborate this last issue and present an excellent overview on both epidemiologic and pathophysiologic data. Another method proposed for primary prevention of preterm birth is the use of progesteron, including vaginal progesteron and systemic 17-hydroxyprogesterone caproate. Starting progesterone treatment can be based not only on cervical length or vaginal fibronectin but also on past obstetrical history. C. E. Ransom et al. comment on the use of 17-hydroxyprogesterone caproate and the influence of obstetric history. Some newer methods are on the border of being introduced to clinical practice; one such candidate is near-infrared spectroscopy. K. M. Power and colleagues present the use of near-infrared spectroscopy of amniotic fluid to assess preterm delivery. Once preterm labour has been established, tocolytics are (all too) often used, and what their exact place in treatment is remains open for discussion. Hubinont and F. Debieve present a concise update on tocolysis. In case preterm delivery seems unavoidable, the optimal mode of fetal monitoring and the mode of delivery have to be chosen. Fetal heart rate monitoring in the preterm period constitutes a special challenge and is further commented by K. Afors and E. Chandraharan, while S. R. Bhatta and C. R. Keriakos discuss the optimal way of delivering the preterm baby in vertex position. As the articles in this issue demonstrate, preterm labour and delivery constitute one of the major challenges of obstetrics in the 21st century. Yves Jacquemyn Ronnie Lamont Jerome Cornette Hanns Helmer

Transvaginal ultrasound of cervical length and its correlation to digital cervical examination, time to spontaneous labor and mode of delivery

The objective of this study was to determine if transvaginal ultrasound (TVUS) examination of cervical length correlates to digital pelvic examination and if it can predict time to and mode of delivery in term pregnancies. We conducted a prospective cohort study of 726 consecutive non-laboring, term pregnant women presenting to University-based antenatal testing unit between 1 July 2001 and 31 March 2002. Subjects underwent a TVUS for cervical length followed by a digital cervical examination by a physician blinded to the results of the ultrasound. Linear regression analysis was used to correlate the findings of cervical length by ultrasound with cervical dilatation and effacement by digital examination. In 726 women, the relationship between TVUS cervical length and cervical dilatation and effacement measured digitally were found to be significantly related (p < 0.001), but weak, with a 15 and 23% goodness of fit, respectively, based on the linear model. Using multivariate logistic and linear regression, respectively, TVUS cervical length predicted mode of delivery but did not predict time to spontaneous labor. Digital measurement of cervical dilatation was predictive of time to spontaneous labor. There is a statistically significant correlation between TVUS measurement of cervical length and digital cervical exam though the correlation is weak. TVUS measurement of cervical length was predictive of mode of delivery while controlling for digital cervical examination, parity and time to spontaneous labor. Digital cervical dilatation was predictive of time to spontaneous delivery.