Evaluation of a New Predictive Test of Preterm Birth in Case of Threatened Preterm Labor

Inclusion Criteria: * Patient aged \> 18 years (with no upper age limit) * Patient affiliated to a social security health regime * Between 24 and 33 + 6 weeks of gestation (amenorrhea) * Singleton pregnancy * Patient with a TPL: Uterine contractions during the last 24 hours felt by the patient, painful or not, and cervix less than or equal to 25 mm on endovaginal ultrasound * Having signed an informed consent form Exclusion Criteria: * Twin pregnancy * Sexual intercourse less than 24 hours from inclusion * Cervical cerclage * Abundant metrorrhagia * Premature rupture of membranes * Pre-eclampsia * Congenital malformation * Presence of a placenta previa * Pelvic examination in the previous 24 hours (compared to inclusion) * Patient under guardianship, curatorship or safeguard of justice * Persons deprived of their liberty by judicial or administrative decision * Persons under psychiatric care under duress