Threatened preterm labor (TPL) is defined by cervical changes and regular and painful uterine contractions occurring between 24 and 36 + 6 weeks of gestation that may or may not lead to premature labor and delivery. There is no reliable way to predict preterm delivery.

The study's hypothesis is that the Premaquick® test can improve the prediction of preterm delivery.

The investigators also want to compare this test with the Partosure® (Placental alpha microglobulin-1) test.

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