Intravaginal drug delivery systems (intravaginal rings; IVRs) are designed to release one or more active pharmaceutical ingredients (APIs) to the vaginal tract and finally into the systemic circulation over extended time periods. From the technological point of view, IVRs are classified into matrix and reservoir type IVRs whereat the majority of marketed IVRs is matrix systems based on silicone, one IVR, a reservoir based system, comprises two types of EVA co-polymer. In matrix systems, the API is homogeneously dispersed throughout the polymer. A route to produce matrix IVRs is hot melt extrusion to obtain drug-loaded polymer intermediates, which are then injection molded to yield the ring shape. The drug release rate is governed by drug diffusion through the polymer. The release rate, following Higuchi’s law, is proportional to the square root of time and is altered by modifications in the surface area, the drug loading and/or the API chemistry. In reservoir system, the polymer core contains the homogeneously dispersed API and is surrounded by drug-free skin. The production route of reservoir systems includes co-extrusion of the layered structure followed by a joining process to obtain the ring. The drug release rate is determined by diffusion through the skin and remains constant (= zero order release). It can be altered by modifications of the skin thickness and/or the API chemistry. Regarding the mechanical properties, the ring is required to be flexible. Prior/during insertion, the IVR has to be easily compressed, followed by fast recovery to remain in the vaginal cavity without causing damage. Yet, the junction deriving from ring closure needs to be strong enough to prevent ring opening. IVR’s mechanical properties can be affected via its formulation. In this study, the impact of process parameters, used polymer (polymer crystallinity) and formulation on mechanical properties of EVA based rings was investigated.