The effectiveness of a birth control method is defined in two ways:
-
Use Effectiveness: How well a birth control method works in ”typical use”, taking into consideration human error and other non ideal factors.
-
Theoretical Effectiveness: How well a birth control method works when it is used correctly and when all other conditions are ideal “perfect use”.
To make an informed choice, both partners need to understand how to use the method correctly and consistently. Effectiveness figures are based on 100 couples using the method for a year and show the percentage of women who do not get pregnant while using the method for 1 year.
| METHOD | USE EFFECTIVENESS (Actual Use) | THEORETICAL EFFECTIVENESS (Perfect Use) |
|---|---|---|
| EVRA PATCH | 92% | 99.7% |
| PILL - Combined - Progestin |
92% 92% |
99.7% 99.7% |
| NUVARING | 92% | 99.7% |
|
IUD
Copper T Levonorgenestrel (Mirena) |
99.2% |
99.4% |
| DIAPHRAGM & SPERMICIDE | 84% | 94% |
| SPERMICIDE & MALE CONDOMS** | no confirmed data | 99% |
| FEMALE CONDOM ALONE | 79% | 95% |
| MALE CONDOM ALONE | 85% | 98% |
| SPERMICIDES*** | 71% | 82% |
| TUBAL LIGATION | 99.5% | 99.5% |
| VASECTOMY | 99.85% | 99.9% |
| CERVICAL CAP Woman has had children Woman has not had children |
68% 84% |
74% 91% |
| DEPO-PROVERA | 97% | 99.95% |
| SPONGE Woman has had children Woman has not had children |
68% 84% |
80% 91% |
| FERTILITY AWARENESS METHOD |
75% |
95-97% |
| WITHDRAWAL | 73% | 96% |
| NO METHOD (CHANCE) | 15% | 15% |
*Adapted from Contraceptive Technology, 19th Revised Edition, Hatcher, et al (New York: 2007).
**Separate spermicide in addition to condoms.
***Foams, creams, gels, vaginal suppositories, and vaginal film.
FS400
Revised March 2009
