Measurement of cervical length with vaginal ultrasound in midgestation in asymptomatic women with a singleton pregnancy to predict preterm delivery

Measurement of cervical length with vaginal ultrasound in the second trimester in asymptomatic women with a singleton pregnancy to predict preterm delivery: a Swedish multi-center observational study

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

ISRCTN

Registry ID

ISRCTN18093885

Enrollment

11000

Registered

2016-09-28

Start date

2014-05-01

Completion date

Unknown

Last updated

2023-10-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pregnancy Pregnancy and Childbirth

Interventions

This is a Swedish multicentre prospective observational study. where healthy asymptomatic women with a singleton pregnancy will be examined with transvaginal ultrasound and measurement of cervical len

Eligibility

Sex/Gender

Female

Inclusion criteria

Inclusion criteria: 1. Asymptomatic women > 18 years old 2. With a live healthy singleton pregnancy in gestational week 18+0-20+6 3. Able to understand oral and written information

Exclusion criteria

Exclusion criteria: 1. Fetal malformation 2. Rupture of membranes 3. Current vaginal bleeding 4. Ongoing miscarriage 5. Cerclage in situ 6. Current progesterone treatment at the time of recruitment

Design outcomes

Primary

Measure	Time frame
Ability of sonographic cervical length to predict preterm birth < 33 weeks, expressed as the area under the receiver operating characteristic curve (ROC) sensitivity, specificity, positive and negative likelhood ratio.	—

Secondary

Measure	Time frame
Ability of sonographic cervical length to predict spontaneous PTB <33 + 0 gestational weeks and for total and spontaneous PTB <28 + 0, <29 + 0, <30 + 0, <31 + 0, <32 + 0, <34 + 0 and< 35 + 0 gestational weeks. All calculations will be made for: 1. the length of the closed cervical canal 2. if the isthmus is present its length is measured separately 3. from the external cervical os to the apparent (virtual) inner cervical os (if isthmus is present) 4. the length of the closed cervical canal + the isthmus. Each measurement is taken three times and all three are recorded. Calculations will be made for the minimum, maximum and mean value and separately for measurements taken at 18 + 0 - 20 + 6 gestational weeks and 21+ 0 - 23 + 6 gestational weeks. using the ROC curves, the optimal method for measuring cervical length (which week, which measurement) and the optimal cervical length cutoff of the optimal method to predict PTB will be identified. The ability of a change in cervical length between the first (at 18 + 0 - 20 + 6) and the second (at 21 + 0 - 23 + 6) cervical length measurement to predict PTB. The prevalence of "short cervix" (using different definitions) will be calculated.	—

Measure

Time frame

Ability of sonographic cervical length to predict spontaneous PTB <33 + 0 gestational weeks and for total and spontaneous PTB <28 + 0, <29 + 0, <30 + 0, <31 + 0, <32 + 0, <34 + 0 and< 35 + 0 gestational weeks. All calculations will be made for: 1. the length of the closed cervical canal 2. if the isthmus is present its length is measured separately 3. from the external cervical os to the apparent (virtual) inner cervical os (if isthmus is present) 4. the length of the closed cervical canal + the isthmus. Each measurement is taken three times and all three are recorded. Calculations will be made for the minimum, maximum and mean value and separately for measurements taken at 18 + 0 - 20 + 6 gestational weeks and 21+ 0 - 23 + 6 gestational weeks. using the ROC curves, the optimal method for measuring cervical length (which week, which measurement) and the optimal cervical length cutoff of the optimal method to predict PTB will be identified. The ability of a change in cervical length between the first (at 18 + 0 - 20 + 6) and the second (at 21 + 0 - 23 + 6) cervical length measurement to predict PTB. The prevalence of "short cervix" (using different definitions) will be calculated.

—

Countries

Sweden

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026