Pharmacokinetic bioequivalence, safety and acceptability of Ornibel®, a new polymer composition contraceptive vaginal ring (etonogestrel/ethinylestradiol 11.00/3.474 mg) compared with Nuvaring®(etonogestrel/ethinylestradiol 11.7/2.7 mg) - Algorta, J; Diaz, M; de Benito, R (Eur J Contracept Reprod Health Care, 2017)