Background Extended use of the combined oral contraceptive pill (COC), defined as taking active pills for at least 28 days, has been used in order to avoid bleeding at important times and to treat gynaecological conditions such as endometriosis. We examined the main issues involved in extended use of the COC and how it has evolved from being one of medicine's best-kept secrets to becoming more widely accepted by women and the medical community.

Study design Literature review, using Medline, Embase, Pubmed, CINHAL Plus, the Cochrane Database of Systematic Reviews and the Ovid database for all relevant clinical trials, systematic reviews, meta-analyses, literature reviews, scientific papers and individual opinions between 1950 and October 2013.

Results Accumulating evidence supports various forms of extended pill use as suitable alternatives to the standard (21/7) regimen. In terms of user preference, much hinges on whether women wish to reduce the frequency or duration of scheduled bleeding on the combined pill. Available data on the safety of extended pill regimens do not give cause for concern, but longer term data should be collected.

Conclusions Information for women considering extended COC regimens should keep pace with research findings to ensure that women and clinicians are better informed about the choices available.