A one-year multicenter study of efficacy and safety of a continuous, low-dose, estradiol-releasing vaginal ring (Estring) in postmenopausal women with symptoms and signs of urogenital aging.
Henriksson L, Stjernquist M, Boquist L, Cedergren I, Selinus I.
Am J Obstet Gynecol. 1996 Jan;174(1 Pt 1):85-92. doi: 10.1016/s0002-9378(96)70378-2.