Cervical Assessment by Supracervical, Cervical and Vaginal Markers: Simultaneous Transvaginal Ultrasound and Inflammatory Proteins Detection

Preterm birth rate in Quebec is 7.2% and, despite extensive research, the rate of preterm birth has risen worldwide over the past decades. Preterm birth is, all over the world, the first cause of perinatal mortality and morbidity. Spontaneous preterm birth (sPTB) groups premature births with intact and ruptured membranes and represents 70% of preterm delivery. The two conditions associated with sPTB share a common physiopathology and a progressive cascade of events. Extensive evidence supports a central role for the production of prostaglandins, inflammatory cytokines and matrix metalloproteinases (MMP) in the cervix and decidua to promote cervical ripening and decidual and fetal membrane activation but, the exact progression of events remains unclear. Several factors were described as risk factor for sPTB like bacterial vaginosis, inflammatory cytokines and fetal fibronectin in vaginal secretions. The transvaginal ultrasound of the cervix (TVUS), which estimates the length and the aspect of the cervix, can be used as predictive factor of preterm birth. To date, no study has addressed the supra-cervical region by transvaginal ultrasound. This region may be an important key of the inflammatory process leading to sPTB. The assessment of this region by ultrasound can be a predictive marker of sPTB. We want to prove the feasibility of this new approach of sPTB prediction : the transvaginal ultrasound assessment of the supracervical and cervical region associated with detection of vaginal inflammation.