Trussell J, Hatcher R A, Cates W, Stewart F H, Kost K
Office of Population Research, Princeton University, NJ 08544.
Stud Fam Plann. 1990 Jan-Feb;21(1):51-4.
This report provides an update of the authors' previous estimates of first-year probabilities of contraceptive failure for all methods of contraception. Estimates are provided of failure during typical use (which includes both incorrect and inconsistent use) and during perfect use (correct use at every act of intercourse). The difference between these two probabilities provides a measure of how forgiving of imperfect use each method is. These revisions are prompted by recent studies that provide the first estimates of failure during perfect use for periodic abstinence and the cervical cap, by more complete evaluations of implants, and by the appearance of the Copper T 380A and disappearance of other IUDs from the US market. Also provided is a more complete explanation of how the previous estimate of the probability of becoming pregnant while relying solely on chance should be interpreted, and this estimate is revised slightly downward.
本报告更新了作者之前对所有避孕方法第一年避孕失败概率的估计。报告给出了典型使用（包括不正确和不持续使用）及完美使用（每次性交时正确使用）期间的失败率估计。这两种概率之间的差异衡量了每种方法对不完美使用的宽容程度。这些修订是由近期研究推动的，这些研究首次给出了周期性禁欲和宫颈帽在完美使用期间的失败率估计，对植入物进行了更全面的评估，以及铜T 380A的出现和其他宫内节育器在美国市场的消失。报告还更全面地解释了仅靠运气怀孕概率的先前估计应如何解读，并且该估计略有下调。
