From Office of Population Research, Princeton University, Wallace Hall, Princeton, New Jersey; Family Health International, Research Triangle Park, North Carolina; The Hull York Medical School, University of Hull, United Kingdom; Shanghai Institute of Planned Parenthood Research, Shanghai, People's Republic of China; Minhang Central Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
Obstet Gynecol. 2010 Jun;115(6):1263-1266. doi: 10.1097/AOG.0b013e3181dd22ef.
To evaluate the existing data to estimate the rate of ectopic pregnancy among emergency contraceptive pill treatment failures.
Our initial reference list was generated from a 2008 Cochrane review of emergency contraception. In August 2009, we searched Biosys Previews, the Cochrane Database of Systematic Reviews, Medline, Global Health Database, Health Source: Popline, and Wanfang Data (a Chinese database).
This study included data from 136 studies, which followed a defined population of women treated one time with emergency contraceptive pills (either mifepristone or levonorgestrel) and in which the number and location of pregnancies were ascertained.
Data from each article were abstracted independently by two reviewers. In the studies of mifepristone, 3 of 494 (0.6%) pregnancies were ectopic; in the levonorgestrel studies, 3 of 307 (1%) were ectopic.
The rate of ectopic pregnancy when treatment with emergency contraceptive pills fails does not exceed the rate observed in the general population. Because emergency contraceptive pills are effective in lowering the risk of pregnancy, their use will reduce the chance that an act of intercourse will result in ectopic pregnancy.
III.
评估现有数据，以估算紧急避孕失败后异位妊娠的发生率。
我们最初的参考文献列表是根据 2008 年 Cochrane 对紧急避孕的综述生成的。2009 年 8 月，我们检索了 Biosys Previews、Cochrane 系统评价数据库、Medline、全球卫生数据库、Health Source: Popline 和万方数据（一个中文数据库）。
本研究纳入了 136 项研究的数据，这些研究随访了一组明确的女性人群，她们单次使用紧急避孕药（米非司酮或左炔诺孕酮），并确定了妊娠的数量和位置。
两名评审员独立摘录了每篇文章的数据。在米非司酮的研究中，494 例妊娠中有 3 例（0.6%）为异位妊娠；在左炔诺孕酮的研究中，307 例妊娠中有 3 例（1%）为异位妊娠。
紧急避孕失败后异位妊娠的发生率并未超过一般人群的发生率。由于紧急避孕药能有效降低妊娠风险，其使用将减少性行为导致异位妊娠的机会。
III。
