FB-CT2 Includes Two Prospective, Multi-centre Studies With a Medical Device in Hospital Settings: a Randomized, Dual-arm, Open-label Pilot Study in Spain, Followed by a Single-arm, Non-randomized, Open-label International Pivotal Study

The goal of this clinical trial is to evaluate the safety and the ability of a clinical investigation device (Cervisense TPTL) to predict the risk of spontaneous preterm birth in pregnant women with symptoms of threatened preterm labor (TPTL), between 28+0 and 36+6 weeks of gestation. The main questions it aims to answer are: Does the Cervisense TPTL device predict spontaneous preterm birth within 7 days? Is the device safe and technically reliable in a hospital setting? Researchers will conduct a Pilot Study (randomized, dual-arm) followed by a Pivotal Study (single-arm) to assess technical feasibility and predictive performance. Participants will undergo an intravaginal measurement of cervical stiffness using the Cervisense Intravaginal Probe. They will be followed for 14 days after the assessment to record delivery outcomes and any adverse events.