The Gatehouse, NHS Ayrshire and Arran, Ayrshire Central Hospital, United Kingdom.
Chalmers Sexual and Reproductive Health Centre, NHS Lothian, 2 A Chalmers Street, Edinburgh, EH3 9ES, United Kingdom; Obstetrics and Gynaecology, University of Edinburgh, United Kingdom.
Best Pract Res Clin Obstet Gynaecol. 2020 Feb;63:111-119. doi: 10.1016/j.bpobgyn.2019.06.008. Epub 2019 Jul 3.
Emergency contraception (EC) is a drug or a device that is taken after sexual intercourse to prevent unintended pregnancy. The most effective EC is the copper-bearing intrauterine device (Cu-IUD), but oral EC methods are more commonly used and include a single dose of either levonorgestrel (1.5 mg) or ulipristal acetate (30 mg). Although all EC methods are extremely safe, access to EC is often limited due to prevailing misconceptions over how EC works. Although EC can prevent unintended pregnancy for an individual woman, it has failed to make an impact on abortion rates at a population level. This may be because it is not used after every episode of unprotected sex and because existing oral EC methods are only effective if used before ovulation. Future strategies around EC should focus on maximising uptake of Cu-IUD, facilitating initiation of effective regular contraception after EC and developing a more effective oral EC.
紧急避孕（EC）是一种在性行为后服用的药物或器具，用于防止意外怀孕。最有效的 EC 是含铜宫内节育器（Cu-IUD），但口服 EC 方法更为常用，包括单次服用左炔诺孕酮（1.5 毫克）或依托孕烯（30 毫克）。虽然所有 EC 方法都非常安全，但由于对 EC 作用机制的普遍误解，EC 的获取往往受到限制。尽管 EC 可以为个别女性预防意外怀孕，但它未能对人口层面的堕胎率产生影响。这可能是因为它并非在每次无保护性行为后都使用，而且现有的口服 EC 方法只有在排卵前使用才有效。未来关于 EC 的策略应侧重于最大限度地提高 Cu-IUD 的使用率，在 EC 后促进有效常规避孕的开始，并开发更有效的口服 EC。
