Cervical Length Measurement Timing for Preterm Birth

Overseen By Raminder Khangura, MD

Age: Any Age

Sex: Female

Trial Phase: Academic

Sponsor: Henry Ford Health System

Disqualifiers: Preterm delivery, Cervical insufficiency, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

550 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores the optimal timing for measuring cervical length during pregnancy scans to predict early birth risk. Researchers are testing whether measurements taken at the start or end of the scan yield better results. They are also comparing two types of ultrasound images: regular grayscale and sepia-filtered. Pregnant individuals between 16 and 23 weeks, attending specific clinics, and consenting to an internal ultrasound, can participate. This research aims to enhance prenatal care by improving early birth risk assessments. As an unphased trial, it allows participants to contribute to advancements in prenatal care without the constraints of traditional clinical trial phases.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It focuses on measuring cervical length during pregnancy and does not mention any medication restrictions.

What prior data suggests that this cervical length measurement technique is safe for pregnant individuals?

Research shows that measuring cervical length with a transvaginal ultrasound is an important predictor of early birth in pregnant individuals. Studies have found this method effective in identifying those at risk for early labor. This procedure is generally comfortable and does not introduce additional risks beyond regular prenatal care.

Patients who previously had their cervical length measured did not experience significant negative effects, confirming its safety for monitoring during pregnancy. The trial aims to determine the optimal timing for measuring cervical length to achieve the most accurate results. Researchers will test different timings and imaging methods, but the safety of the measurement itself is well-established. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores the optimal timing for cervical length measurement to predict preterm birth risk. Unlike standard practices that may not specify the timing of these measurements during the anatomy survey, this trial tests whether taking measurements at the beginning versus the end can improve adherence to the CLEAR criteria for accuracy. By using both grayscale and sepia-filtered ultrasound imaging, the trial aims to enhance the precision of cervical length assessments, potentially leading to better early detection and management of preterm birth risks.

What evidence suggests that this trial's cervical length measurement methods could be effective for improving preterm birth risk assessment?

Research has shown that checking cervical length can help predict early births. One study found that measuring it once between 18 and 24 weeks of pregnancy is effective. This approach might be more effective than multiple checks. Another study found that using a transvaginal ultrasound to measure cervical length is especially helpful for women expecting twins. In this trial, participants will be divided into two groups: one group will have cervical length measured at the start of the anatomy scan, and the other at the end. The trial examines whether the timing of the measurement affects accuracy and if sepia-toned images improve accuracy compared to regular black-and-white images. ^{6 7 8 9 10}

Who Is on the Research Team?

Raminder Khangura, MD

Principal Investigator

Henry Ford Health

Are You a Good Fit for This Trial?

This trial is for pregnant individuals undergoing routine fetal anatomy surveys. It's designed to find the best time to measure cervical length, which helps predict preterm birth risk. Participants must consent to a transvaginal ultrasound and be okay with being randomly assigned when their cervical length will be measured.

Inclusion Criteria

Agreement to participate in the study, including randomization for the timing of cervical length measurement

Presenting for a fetal anatomy survey at Henry Ford Health MFM ultrasound units

Consent to a transvaginal cervical length measurement as part of routine care

Exclusion Criteria

Patients receiving care at non-Henry Ford Health radiology clinics

History of preterm delivery

Declines or unable to consent to a transvaginal cervical length measurement

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

1 visit (in-person)

Randomization and Intervention

Participants are randomized to have cervical length measured at either the start or end of the anatomy survey using both grayscale and sepia-filtered ultrasound imaging.

1 day

1 visit (in-person)

Data Collection and Analysis

Cervical length measurements are collected and analyzed for adherence to the nine CLEAR criteria.

1-2 weeks

Follow-up

Participants are monitored for any adverse effects and the study outcomes are evaluated.

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Cervical Length Measurement

Trial Overview The study tests whether measuring cervical length at the start or end of an anatomy survey affects its accuracy, using both grayscale and sepia-filtered ultrasound images. The goal is to determine if timing and imaging method can improve detection of potential preterm births.

How Is the Trial Designed?

Group I: End of Anatomy Survey Experimental Treatment 1 Intervention

Participants in this arm will undergo cervical length measurement via transvaginal ultrasound at the end of the fetal anatomy survey. This timing aims to evaluate whether late measurement improves adherence to the nine CLEAR criteria for accurate cervical length assessment. Measurements will also be conducted using grayscale and sepia-filtered ultrasound imaging.

Group II: Beginning of Anatomy Survey Experimental Treatment 1 Intervention

Participants in this arm will undergo cervical length measurement via transvaginal ultrasound at the start of the fetal anatomy survey. This timing aims to evaluate whether early measurement improves adherence to the nine CLEAR criteria for accurate cervical length assessment. Measurements will also be conducted using grayscale and sepia-filtered ultrasound imaging.

Who Is Running the Clinical Trial?

Henry Ford Health System

Lead Sponsor

Trials

334

Recruited

2,197,000+

Published Research Related to This Trial

Transvaginal ultrasonography is a reliable method for assessing cervical length and predicting preterm delivery risk in high-risk pregnancies, with a cervical length of 25 mm or less at 28-30 weeks significantly increasing the risk of preterm delivery.

While cervical length measurement (CLM) is effective in high-risk groups, it has low sensitivity in low-risk populations, and current recommendations suggest using it as a routine method for high-risk pregnancies rather than a general screening tool.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cervical length assessment by ultrasound as a predictor of preterm labour--is there a role for routine screening? Hoesli, I., Tercanli, S., Holzgreve, W.[2019]

In a study of 122 women with threatened preterm labor, a cervical length measurement of less than 15 mm at presentation was found to have high sensitivity (83.3%) and specificity (95.8%) for predicting delivery within one week.

A significant reduction of more than 20% in cervical length within 24 hours also indicated a risk for preterm delivery, but did not enhance prediction accuracy when combined with initial measurements.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The value of serial cervical length measurements for the prediction of threatened preterm labour. Sotiriadis, A., Kavvadias, A., Papatheodorou, S., et al.[2016]

In a study of 11,943 women, mid-trimester cervical length (CL) measurements were found to be predictive of spontaneous preterm birth, with likelihood ratios indicating a strong association for very short cervixes (≤ 20 mm) in nulliparous women.

Despite its predictive capacity, the isolated use of CL as a screening tool has limited value due to low sensitivity, with a high number needed to screen (618 for nulliparous and 1417 for low-risk multiparous women) to prevent one case of preterm birth.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The capacity of mid-pregnancy cervical length to predict preterm birth in low-risk women: a national cohort study. van der Ven, J., van Os, MA., Kazemier, BM., et al.[2016]

Ultrasonographic measurement of cervical length is a valuable tool for predicting preterm birth, helping to identify women at risk and potentially reducing rates of prematurity.

The review suggests that appropriate interventions based on cervical length measurements may prevent unnecessary medical procedures and improve outcomes for at-risk pregnancies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

No. 257-Ultrasonographic Cervical Length Assessment in Predicting Preterm Birth in Singleton Pregnancies. Lim, K., Butt, K., Crane, JM.[2019]

Ultrasonographic measurement of cervical length can effectively predict the risk of preterm birth, helping to identify women who may need closer monitoring or intervention.

Implementing this technique may lead to a reduction in preterm birth rates and prevent unnecessary medical interventions, ultimately improving maternal and fetal outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

SOGC Clinical Practice Guideline. Ultrasonographic cervical length assessment in predicting preterm birth in singleton pregnancies. Lim, K., Butt, K., Crane, JM.[2017]

A systematic review identified 12 articles discussing the effects of transvaginal cervical length measurement in women with symptoms of preterm labor, highlighting potential benefits like patient reassurance, but none quantified these effects.

There is a notable gap in the literature regarding the assessment of additional patient outcomes from cervical length measurements, suggesting that future studies should include comprehensive evaluations of these effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Additional effects of the cervical length measurement in women with preterm contractions: a systematic review. Vis, JY., Kuin, RA., Grobman, WA., et al.[2021]

In a study of 216 pregnant women, cervical length measured at 21-24 weeks of gestation was found to be a significant predictor of preterm delivery, while measurements taken at 14-16 weeks were not effective in predicting this outcome.

The change in cervical length between the two measurements did not correlate with the risk of preterm delivery, indicating that monitoring cervical length later in pregnancy is more crucial for assessing the risk of preterm birth.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Can sonographic measurements and changes in cervical length during pregnancy predict preterm labour in an asymptomatic low-risk population? Weitzner, O., Biron-Shental, T., Daykan, Y., et al.[2019]

In a study of 42 women with singleton pregnancies between 24 to 34 weeks gestation, clinician digital examinations significantly underestimated cervical length (CL) compared to objective measurements using the Cervilenz device, with an average difference of 0.52 cm.

The discrepancy in CL measurements was notable, as 36% of subjects had differences exceeding 1 cm, indicating that the Cervilenz device provides a more accurate assessment for women presenting with symptoms of preterm labor.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Blinded comparison of cervical portio length measurements by digital examination vs Cervilenz. Burwick, RM., Lee, GT., Benedict, JL., et al.[2019]

Sonography-derived cervical length measurements can effectively identify women at increased risk of preterm birth, potentially leading to interventions that may reduce the rates of prematurity.

The review highlights various techniques for measuring cervical length using sonography, emphasizing their clinical utility in managing patients at risk for a short cervix and preterm birth.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Guideline No. 401: Sonographic Cervical Length in Singleton Pregnancies: Techniques and Clinical Applications. Lim, KI., Butt, K., Nevo, O., et al.[2021]

In a study analyzing 983 cervical length measurements, blinding the operator during mid-trimester scans resulted in a higher prevalence of short cervix (5.5%) compared to non-blinded measurements (2.7%), indicating that observer bias can significantly affect results.

Blinding also led to a more normal distribution of cervical length values, suggesting that it is an effective strategy to enhance the accuracy of cervical length screening for preterm birth risk.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Expected-value bias in mid-trimester preterm birth screening. Aiartzaguena, A., Del Campo, A., Melchor, I., et al.[2022]

In a study of 1,180 low-risk singleton pregnancies, cervical length (CL) measurements taken between 24 and 30 weeks gestation were found to be significantly shorter in women who experienced spontaneous preterm delivery (SPD) between 30-34 weeks and 34-37 weeks, indicating that shorter CL is a strong predictor of early delivery.

The study demonstrated that CL is highly effective in predicting SPD34 with an area under the curve (AUC) of 0.9406, and adequately predicts SPD37 with an AUC of 0.7584, suggesting that monitoring CL can help identify pregnancies at risk for preterm delivery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prediction of Preterm Delivery by Late Cervical Length Measurement after 24 Weeks. Papastefanou, I., Pilalis, A., Eleftheriades, M., et al.[2016]

In a study of 1113 low-risk women, cervical length (CL) measured at 11-14 weeks showed a small predictive value for preterm delivery (PTD) before 37 weeks, with a sensitivity of only 63.3% and specificity of 51.1%.

However, CL measurements did not predict PTD for deliveries before 35 weeks or 32 weeks, indicating that while there may be some correlation with PTD <37 weeks, it is not a reliable indicator for earlier preterm deliveries.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The role of cervical length measurement at 11-14 weeks for the prediction of preterm delivery. Antsaklis, P., Daskalakis, G., Pilalis, A., et al.[2019]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4675685/

A SYSTEMATIC REVIEW AND META-ANALYSIS A single cervical length measurement obtained between 18–24 weeks of gestation appears to be a better test to predict preterm birth than changes in cervical ...

2. sciencedirect.com sciencedirect.com/science/article/abs/pii/S2589933324000697

Universal cervical length screening and risk of ... In the overall analysis, universal transvaginal ultrasound cervical length did not significantly decrease the spontaneous preterm birth rates <37 weeks (odds ...

3. nature.com nature.com/articles/s41598-021-86906-8

Mid-trimester prediction of spontaneous preterm birth with ... The objective of this study was to evaluate a novel automated test based on ultrasound cervical texture analysis to predict spontaneous Preterm Birth (sPTB)

4. ajog.org ajog.org/article/S0002-9378(16)30112-0/fulltext

The role of routine cervical length screening in selected high The purpose of this document is to review the indications and rationale for cervical length screening to prevent preterm birth in various clinical scenarios.

5. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3147231/

TRANSVAGINAL SONOGRAPHIC CERVICAL LENGTH ... Transvaginal sonographic CL 20-24 weeks' gestation is a good predictor of spontaneous preterm birth in asymptomatic women with twin pregnancies.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4810783/

Universal Cervical Length Screening: Implementation and ... Rates of spontaneous preterm birth before 28 weeks were higher in those who declined cervical length screening (aOR 2.01, 95% CI 1.33, 3.02). Conclusion.

7. obgyn.onlinelibrary.wiley.com obgyn.onlinelibrary.wiley.com/doi/full/10.1002/uog.7457

Transvaginal cervical length measurement for prediction of ... A cut-off of 15 mm for cervical length (three studies, 1266 women, rate of preterm birth within 48 h 7.1%) predicted 71.1% (95% CI, 59.5–80.9%) ...

8. bmcpregnancychildbirth.biomedcentral.com bmcpregnancychildbirth.biomedcentral.com/articles/10.1186/s12884-025-08210-x

First-trimester cervical length screening and the risk of preterm ... The analysis revealed that pregnant individuals who underwent PTB before 37- and 34-weeks' gestation exhibited significantly shorter CL during ...

9. sdms.org sdms.org/docs/default-source/jdmspdf/serial-cervical-length-measurement-for-determining.pdf?sfvrsn=2

Serial Cervical Length Measurement for Determining the ... Objective: This study aimed to evaluate whether serial evaluations of cervical length (CL) have the potential to determine preterm labor in women with ...

10. ajog.org ajog.org/article/S0002-9378(24)00588-X/fulltext

SMFM Consult Series #70: Management of short cervix in ... Midtrimester cervical length assessment using transvaginal ultrasound is one of the best clinical predictors of spontaneous preterm birth. This ...