Hi,
i found this at http://www.4woman.Gov/faq/contraception.Ht m I just thought it was important for people to know what kind of failure rates their method of choice have. We are often told the theoretical failure rate (ie. In a lab with perfect use) but not the "typical use". Just thought i'd share since I found this very interesting.
~laura




sterilization:

male sterilization: typical use rate of pregnancy, 0.15%; lowest expected rate of pregnancy, 0.1%
female sterilization: typical use rate of pregnancy, 0.5%; lowest expected rate of pregnancy, 0.5%

hormonal methods:

implant (norplant): typical use rate of pregnancy, 0.09%; lowest expected rate of pregnancy, 0.09%
hormone shot (depo-provera): typical use rate of pregnancy, 0.3%; lowest expected rate of pregnancy, 0.3%
combined pill (estrogen/progestin): typical use rate of pregnancy, 5%; lowest expected rate of pregnancy, 0.1%
minipill (progestin only): typical use rate of pregnancy, 5%; lowest expected rate of pregnancy, 0.5%

intrauterine devices (iuds):

copper t: typical use rate of pregnancy, 0.8%; lowest expected rate of pregnancy, 0.6%
progesterone t: typical use rate of pregnancy, 2%; lowest expected rate of pregnancy, 1.5%

barrier methods:

male latex condom¹: typical use rate of pregnancy, 14%; lowest expected rate of pregnancy, 3%
diaphragm²: typical use rate of pregnancy, 20%; lowest expected rate of pregnancy, 9%
vaginal sponge (no previous births)³: typical use rate of pregnancy, 20%; lowest expected rate of pregnancy, 9%
vaginal sponge (previous births)³: typical use rate of pregnancy, 40%; lowest expected rate of pregnancy, 20%
cervical cap (no previous births)²: typical use rate of pregnancy, 20%; lowest expected rate of pregnancy, 9%
cervical cap (previous births)²: typical use rate of pregnancy, 40%; lowest expected rate of pregnancy, 26%
female condom: typical use rate of pregnancy, 21%; lowest expected rate of pregnancy, 5%

spermicide: (gel, foam, suppository, film): typical use rate of pregnancy, 26%; lowest expected rate of pregnancy, 6%

natural methods:

withdrawal: typical use rate of pregnancy, 19%; lowest expected rate of pregnancy, 4%
natural family planning (calendar, temperature, cervical mucus): typical use rate of pregnancy, 25%; lowest expected rate of pregnancy, 1-9%
no method: typical use rate of pregnancy, 85%; lowest expected rate of pregnancy, 85%

¹without spermicide, ²with spermicide, ³contains spermicide