The study aimed to evaluate whether the EVA membrane’s compositions of two different contraceptive vaginal rings could influence the surface roughness, which is associated with the possible accumulation of vaginal biomass on the coils during use.

We measured and compared the surface roughness of new vaginal rings, NuvaRing and Ornibel, using an SEM and dedicated software to convert SEM images into 3D models. Average roughness (Ra), average quadratic roughness (Rq), and mean Researchers calculated the height of the irregularities at 10 points (Rz).

Researchers noted different thicknesses of the EVA membranes between the two rings. Researchers found no significant differences between the two rounds in the three evaluated values of surface roughness (NuvaRing vs. Ornibel, respectively: Ra, 1.53 ± 0.14 vs. 1.61 ± 0.14 µm, p = 0.141; Rq, 2.03 ± 0.25 vs. 2.07 ± 0.16 µm, p = 0.688; Rz, 11.4 ± 3.1 vs. 11.4 ± 2.4 µm, p = 0.987).The different composition of the vaginal rings’ EVA membrane is not associated with different surface roughness. Ornibel is equivalent to NuvaRing in terms of surface roughness, despite the membrane polymers’ diverse composition.