WOMEN'S HEALTH Risk of Pregnancy Among Women Seeking Emergency Contraceptives From Pharmacists in British Columbia

Objective: Recent revision of the method used to estimate risk of pregnancy among women requesting medication for emergency contraception (EC) suggests that the effectiveness of EC may be lower than is generally believed. We undertook a population-based study to estimate the risk of pregnancy among women requesting EC from pharmacists in British Columbia under conditions of routine care. Methods: We obtained data on time since unprotected intercourse and medication provided for women in British Columbia requesting EC from January 1, 2001 to December 31, 2002. Results: More women obtained levonorgestrel (60.7%) than the Yuzpe regimen (39.3%) for EC, and of those reporting contraceptive failure, 90 % requested EC because of condom failure. Overall, the estimated risk of pregnancy among the 11 795 women who obtained EC was 4.12 % (95 % confidence interval 3.77–4.49). Conclusion: Under routine conditions, the population-based predicted risk of pregnancy is lower than has previously been estimated. This suggests that the relative reduction in pregnancies achieved with EC is lower than is currently assumed by clinicians and patients. Résumé Objectif: La révision récente de la méthode utilisée pour estimer le risque de grossesse chez les femmes qui demandent une contraception d’urgence (CU) semble indiquer que celle-ci pourrait être moins efficace que ce que l’on croyait. Nous signalons les résultats avons mené une étude visant l'obtention d’une estimation en population générale du risque de grossesse chez les femmes qui adressent une demande de CU, auprès des pharmaciens de la Colombie-Britannique, dans le cadre des soins habituels. Méthodes: Nous avons obtenu des données (couvrant la période allant du 1 e