Fig. 1
a) Materials for silicone production: support cylinder and mold; b) dimensions of the support cylinder and of the cervix model; c) cervix model; d) five cervix models produced e) Cervical Stiffness Index (pcl in mbar) at different gestational ages (from Badir et al., 2013 [10], blue bars, mean ± standard deviation) and closing pressure of the five silicone cervices produced (pink dots)