Effectiveness, safety and acceptability of continuous or extended-cycle use of combined oral contraceptives (COCs): a systematic review and meta-analysis.
BACKGROUND To evaluate the contraceptive effectiveness, safety and acceptability of continuous or extended-cycle combined oral contraceptives (COCs) compared with conventional cyclic regimens (21/7 or 24/4). METHODS A systematic search was conducted in Medline, Embase, Web of Science, trials registries and other data...