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Schwangerschaftsvorsorge Pregnancy care Soins prénataux

Pregnolia has developed a medical device for the improvement of pregnancy care. The device is the result of several years of academic research at ETH Zürich and University Hospital Zürich and allows to measure cervical stiffness. 


  • quantitative und objective measurement of cervical stiffness

  • safe and simple application

  • takes only a few minutes

  • high resolution stiffness scale and less intrusive than digital palpation

how the device works

The Pregnolia System consists of a single-use sterile probe and a control unit. The probe is placed on the anterior lip of the cervix with the help of a speculum. The measurement is started by operating the foot switch, creating a weak vacuum inside the probe that pulls the tissue in. The softer the tissue, the weaker the vacuum required to deform the cervical tissue by 4mm. Within a few seconds, the device completes this procedure and displays the cervical stiffness index (CSI) as a negative pressure value (pcl in mbar).

Funktionsprinzip der Zervixsteifigkeitsmessung Operating principle of the cervical stiffness measurement Principe de fonctionnement de la mesure de la rigidité du col utérin
The cervix softens before it shortens
The cervical stiffness is more predictive than cervical length


A prototype of the device was tested in 2010–2012 in a feasibility study carried out on 50 non-pregnant women and 50 pregnant women. The aim was to record the changes in cervical stiffness throughout a normal pregnancy. The study showed that as pregnancy progresses, the cervix becomes softer, requiring less and less negative pressure to pull the tissue into the probe. The cervix softens even before it shortens (Figure 1). This allows the Pregnolia System to detect changes in the cervical tissue earlier than by measuring the cervical length with ultrasound  [1].

Clinical data (n=1115) have shown [2] that pregnant women with a soft cervix are much more likely to have spontaneous preterm births than women with physiological cervical maturation (Figure 2).

In the multi-center clinical study "SoftCervix" [3], research is currently being conducted into how the length and stiffness of the cervix correlate with the time of birth. The results of the study are expected to be available in 2021.

[1] Badir, S. et al. (2013). Cervical softening occurs early in pregnancy: characterization of cervical stiffness in 100 healthy women using the aspiration technique. Prenat Diagn, 33(8), 737–741

[2] Parra-Saavedra, M. et al. (2011). Prediction of preterm birth using the cervical consistency index. Ultrasound Obstet Gynecol, 38(1), 44–51


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