Anthrax Toxin Receptor 2 Knock-Out and Wild Type Mouse Cervix Exhibit Time-Dependent Mechanical Properties

The cervix plays a critical role during pregnancy, acting as a mechanical barrier to keep the fetus inside the uterus until term. In a normal pregnancy, it is hypothesized that the cervix gradually softens until uterine contractions occur. At this point, the cervix dramatically ripens and dilates for delivery. Similar to other collagenous tissues, the extracellular matrix (ECM) is the load-bearing component of cervical tissue. It is composed mainly of a cross-linked network of fibril forming collagen, types I and III, embedded in a viscous proteoglycan ground substance. Studies conducted on animal models suggest that during normal maturation, a shift in ECM components facilitate cervical softening. However, quantitative cervical softness measurements (i.e. material properties) of these previous studies are ill-defined, limiting the comparative ability of the outcome values. Therefore, our goal is to quantify sensitive and specific time-dependent material properties utilizing mouse models of normal and abnormal pregnancy. Our aim is to discern the role of ECM maintenance in cervical softening.