Assessment of cervical SofTening and the Prediction of Preterm birth

Preterm birth (PTB) is amongst the leading causes of perinatal and childhood
morbidity and mortality. Therefore, accurate identification of pregnant women
at high risk of PTB is important. Identifying these women, enables obstetric
healthcare professionals to apply interventions to postpone delivery and/or to
prevent PTB to improve perinatal and childhood outcomes.
Currently, transvaginal cervical length measurement is used to screen
asymptomatic pregnant women with a history of PTB to identify women requiring a
cerclage. In symptomatic women, presenting with threatened (PTB), cervical
length in combination with the fibronectin test is used to identify women at
high risk to deliver within 7 days of presentation.. However, the predictive
capacity of transvaginal cervical length measurement is limited. In pregnant
women with a history of PTB, it only identifies a proportion of women who will
have recurrent PTB. For symptomatic women, 30-60% of these women admitted to
the hospital, do not deliver within seven days, leading to overtreatment of
these women.
Since cervical softening is a precursor of cervical shortening, effacement and
dilatation, cervical softening is a promising new marker that is based on
tissue elasticity. It can be measured with the CE-marked Pregnolia® System for
accurate characterization of cervical softening status. It provides a value for
tissue elasticity on a continuous scale.
A previous study has shown that softening of the cervix can be detected before
shortening of the cervix. The Pregnolia® System may allow to detect women at
risk for PTB earlier compared to traditional transvaginal ultrasound that
measures shortening of the cervix, and therefore may prove useful for a more
accurate risk assessment of PTB.

The aim of this study is to evaluate the predictive capacity of cervical
softening and risk of PTB.

single centre prospective cohort study.
The Pregnolia® System will be investigated in two different cohorts:
1. Asymptomatic women with a history of PTB
2. Symptomatic women with symptoms of threatened PTB

Asymptomatic cohort:
Standard care for participating women encompasses biweekly visits to the
Preterm Birth Clinic of the Amsterdam UMC. As part of routine care a
transvaginal cervical length measurement is performed to screen for short
cervical length. In case of participation in the study, cervical softening will
be measured simultaneously.

Symptomatic cohort:
All women presenting with threatened PTB undergo transvaginal cervical length
measurement and a fetal fibronectin test (fFN-test) to assess the risk of
delivery within seven days. During this risk assessment cervical softening will
be measured simultaneously.

Procedure of Pregnolia® System:
The procedure is equal for both cohorts and consists of speculum placement and
measurement of cervical softening with the CE-marked Pregnolia® System for
accurate characterization of cervical softening. The procedure is completed
within 75 seconds and is pain free and harmless

Other study procedures:
In both cohorts a structured questionnaire will be used to screen for
additional risk factors for PTB. Patient experience will be monitored as well
as information on safety of the cervical softening measurement.

Benefit and harm:
There is no direct benefit from participation because obstetric healthcare
providers will be blinded for the results of the cervical softening
measurement. However the burden and risks for participating women will be
minimal. Provided care will be according to current national and international
guidelines.