@article {Murphyjfprhc-2017-101740, author = {Lauren EE Murphy and Zhong E Chen and Valerie Warner and Sharon T Cameron}, title = {Quick starting hormonal contraception after using oral emergency contraception: a systematic review}, elocation-id = {jfprhc-2017-101740}, year = {2017}, doi = {10.1136/jfprhc-2017-101740}, publisher = {British Medical Journal Publishing Group}, abstract = {Introduction Unprotected intercourse after oral emergency contraception (EC) significantly increases pregnancy risk. This underlies the importance of promptly starting effective, ongoing contraception {\textendash} known as {\textquoteleft}quick starting{\textquoteright}. However, theoretical concern exists that quick starting might interact with EC or hormonal contraception (HC) potentially causing adverse side effects.Method A systematic review was conducted, evaluating quick starting HC after oral EC [levonorgestrel 1.5 mg (LNG) or ulipristal acetate 30 mg (UPA)]. PubMed, EMBASE, The Cochrane Library, ICTRP, ClinicalTrials.gov and relevant reference lists were searched in February 2016. A lack of comparable studies prevented meta-analysis.Results Three randomised controlled trials were identified. Two biomedical studies suggested HC action was unaffected by quick starting after UPA; one study examined ovarian quiescence (OR 1.27; 95\% CI 0.51{\textendash}3.18) while taking combined oral contraception (COC). Another assessed cervical mucus impenetrability (OR 0.76; 95\% CI 0.27{\textendash}2.13) while taking progestogen-only pills (POP). Quick starting POP reduced the ability of UPA to delay ovulation (OR 0.04; 95\% CI 0.01{\textendash}0.37). Side effects (OR 1.22; 95\% CI 0.48{\textendash}3.12) and unscheduled bleeding (OR 0.53; 95\% CI 0.16{\textendash}1.81) were unaffected by quick starting COC after UPA. Another study reported higher self-reported contraceptive use at 8 weeks among women quick starting POP after LNG, compared with women given LNG alone (OR 6.73; 95\% CI 2.14{\textendash}21.20).}, issn = {1471-1893}, URL = {https://srh.bmj.com/content/early/2017/06/29/jfprhc-2017-101740}, eprint = {https://srh.bmj.com/content/early/2017/06/29/jfprhc-2017-101740.full.pdf}, journal = {BMJ Sexual \& Reproductive Health} }