title: Clinical investigation of a low-dose levonorgestrel-releasing vaginal ring.
abstract: Contraceptive effectiveness and adverse effects were observed in 108 women who used the levonorgestrel-releasing vaginal ring. One-year cumulative net rates per 100 women were pregnancy, 3.7; expulsion, 4.6; use-related discontinuation, 26.9; and continuation, 71.2. The main adverse effects were menstrual disturbances, which improved after longer usage. The menstrual blood loss (MBL), hemoglobin (Hb), and ferritin concentrations were determined in 20 women. The MBL gradually declined after insertion of the vaginal ring and the Hb concentration was significantly increased in the 6th and 12th periods after insertion (P less than 0.05).
mesh_terms: D000328:Adult; D002681:China; D002986:Clinical Trials as Topic; D003267:Contraception; D005260:Female; D006801:Humans; D016912:Levonorgestrel; D008599:Menstruation Disturbances / Q000209:etiology; D009644:Norgestrel / Q000008:administration & dosage*; D010570:Pessaries
chemical_list: D009644:Norgestrel; D016912:Levonorgestrel