But people aren't perfect, so in real life condoms are about 85% effective — that means about 15 out of 100 people who use condoms as their only birth control method will get pregnant each year. The better you are about using condoms correctly every time you have sex, the better they'll work.

Can you get pregnant using a condom even if it doesn't break?

Even if the condom didn't break, pregnancy is still possible. That's because condoms don't work all of the time. If used perfectly, condoms worn on the penis are 98 percent effective at preventing pregnancy.

How do condoms fail?

Some of the most frequent mistakes include putting a condom on partway through intercourse or taking it off before intercourse is over, failing to leave space at the tip of the condom for semen, and failing to look for damage before use.