Contraceptive Failure Rates: Results from a French Population-Based Survey

Caroline Moreau, Princeton University
Jean Bouyer, Institut National de la Santé et de la Recherche Médicale (INSERM)
Germán Rodríguez, Princeton University
James Trussell, Princeton University

Despite the widespread use of highly effective contraceptive methods in France (82% of contraceptive users use a medical contraceptive), one in every three pregnancies is unintended. Of these pregnancies, 65% occur among women who were using contraceptives. This study provides estimates of method-specific failure rates among women in France. We use data from the Cocon Study, a population-based cohort, comprising a representative sample of 2,863 women aged 18-44. Random effect hazards models were used to estimate method-specific contraceptive failure rates during the first five years of contraceptive use. Overall, 2.9% of women experienced a contraceptive failure in the first year of use. The IUD had the lowest first year failure rate (1.1%), followed by the pill (2.4%), the condom (3.3%), fertility awareness methods (7.7%), withdrawal (10.1%), and spermicides (21.4%). These lower failure rates among French women compared to those reported for US women suggest differences in contraceptive practices which need to be further explored.