Table 5

 Failure rates of different contraceptive methods (adapted from Trussell10)

Contraceptive methodPercentage of women with unintended pregnancy within the first year of use
Typical usePerfect use
COC, combined oral contraceptive (estrogen and progestogen); IUD, copper intrauterine device; IUS, levonorgestrel intrauterine system; POP, progestogen-only pill.
*The data on the new POP, Cerazette, are from a different source than the other contraceptive methods in this table and may not therefore be directly comparable. Being from a single study, the Cerazette data are more likely to represent ideal use than typical use. Nonetheless, the efficacy of Cerazette may prove to be greater than both the COC and Depo Provera, because it is taken continuously, without a break, and does not rely on remembering to start a new pack after a week’s break or on returning every 12 weeks for a repeat injection.
No method8585
Standard POP5–100.5
Depo Provera30.3
“Traditional” copper IUD0.80.6
Mirena IUS0.10.1
Female sterilisation0.50.5
Male sterilisation0.150.15