New estimates of the effectiveness of the Yuzpe regimen of emergency contraception

摘要: The purpose of this study was to provide new estimates the effectiveness Yuzpe method emergency contraception and offer correctly computed confidence intervals for estimated rates. Through a literature search, seven studies that present number women treated outcome treatment by cycle day unprotected intercourse relative expected ovulation were identified. Probabilities conception among not using associated variance-covariance matrix from five other datasets estimated, these external used assess regimen. 40 effectiveness, based on separate combined different sets probabilities day, ranged low 44.2% high 88.7%. preferred point estimate is contraceptive pills reduce risk pregnancy 75.4%, with 95% interval extending 65.6% 82.4%. True likely be at least 75% because failures (observed pregnancies) include who already pregnant when became after being treated.