Everyone has that story: The friend who became pregnant at 45 after her husband got a vasectomy. Or the woman who had a baby after having her tubes tied. The friend who had twins nine months after getting an IUD. Paranoid Google searches only confirm our worst fears and perhaps, our greatest hopes.
Statistically, however, those scenarios are extremely unlikely. From the patch to the pill, most birth control methods have a very high effectiveness rating, rarely ever dipping below 80 percent. But imperfect use and other factors, such as whether you’ve had children before or accidentally forget to take your pill for a day, can impact the efficacy of your birth control.
For example, the efficacy of the cervical cap and the sponge for actual use in women who have had children is 68 percent. Meanwhile, the Mirena IUD and a vasectomy are the most effective at 99.9 percent for perfect (meaning ideal) and actual use, which factors in human error and more closely reflects typical use.
Below are data from Options for Sexual Health, a nonprofit in British Columbia, on how effective each form of birth control is with perfect and actual use. If you still need help considering which form of birth control is right for you, the Planned Parenthood website has a thorough run-down of each option. Additionally, The Society of Obstetricians and Gynaecologists of Canada has an online quiz to help you get started. To better understand how to use your form of birth control effectively, talk to your health provider.
Evra patchPerfect use: 99.7%
Actual use: 92%
The pill
Perfect use: 99.7%
Actual use: 92%
Nuvaring
Perfect use: 99.7%
Actual use: 92%
Copper T IUD
Perfect use: 99.4%
Actual use: 99.2%
Mirena IUD
Perfect use: 99.9%
Actual use: 99.9%
Diaphragm and spermicide
Perfect use: 94%
Actual use: 84%
Spermicide and male condoms
Perfect use: 99%
Actual use: No data
Female condoms
Perfect use: 95%
Actual use: 79%
Spermicides
Perfect use: 82%
Actual use: 71%
Tubal ligation
Perfect use: 99.5%
Actual use: 99.5%
Vasectomy
Perfect use: 99.9%
Actual use: 99.9%
Cervical cap
Perfect use in a woman who has had children: 74%
Actual use in a woman who has had children: 68%
Perfect use in a woman who has not had children: 91%
Perfect use in a woman who has not had children: 84%
Depo-Provera
Perfect use: 99.95%
Actual use: 97%
Sponge
Perfect use in a woman who has had children: 80%
Actual use in a woman who has had children: 68%
Perfect use in a woman who has not had children: 91%
Perfect use in a woman who has not had children: 84%
Fertility Awareness Method
Perfect use: 95-97%
Actual use: 75%
Withdrawal or the Pull-Out Method
Perfect use: 96%
Actual use: 73%
No Method
15%