Bastianelli Carlo, Farris Manuela, Benagiano G
Department of Gynaecologic Sciences, Perinatology and Child Care, University la Sapienza, Rome, Italy.
Eur J Contracept Reprod Health Care. 2008 Mar;13(1):9-16. doi: 10.1080/13625180701781096.
Emergency contraception (EC), also known as 'the morning after pill', or post-coital contraception, is a modality of preventing the establishment of a pregnancy after unprotected intercourse. Both a hormonal and an intrauterine form are available. Modern hormonal EC, with low side effects, was first proposed by Yuzpe in 1974. More recently, a new regimen, consisting of levonorgestrel administered alone, was introduced and found in clinical trials to be more effective (if taken as early as possible), and associated with less side effects than the Yuzpe regimen, which it has gradually replaced. The WHO developed another regimen based on the use of the selective progesterone receptor modulator (antiprogestin) mifepristone and conducted trials with different dosages. Intrauterine EC was first proposed by Lippes in 1976. It has the advantage of being applicable for almost a week and the disadvantage of a greater complexity. In addition, this modality is solely interceptive, acting by preventing implantation. Pregnancy rates reported following EC using an intrauterine device with more than 300 mm2 of copper are consistently low (0.1-0.2%).
紧急避孕（EC），也被称为“事后避孕药”或性交后避孕，是一种在无保护性交后防止怀孕的方法。有激素和宫内节育器两种形式。现代激素紧急避孕副作用小，由尤兹佩于1974年首次提出。最近，一种新的方案被引入，该方案仅使用左炔诺孕酮，临床试验发现其更有效（如果尽早服用），且副作用比尤兹佩方案少，已逐渐取代了后者。世界卫生组织基于使用选择性孕激素受体调节剂（抗孕激素）米非司酮制定了另一种方案，并进行了不同剂量的试验。宫内节育器紧急避孕由利佩斯于1976年首次提出。其优点是适用期近一周，缺点是更为复杂。此外，这种方法只是一种阻断措施，通过防止着床起作用。使用含铜面积超过300平方毫米的宫内节育器进行紧急避孕后的妊娠率一直很低（0.1%-0.2%）。
