Scarleteen

Can u easily tell if a condom is broken or not after having sex?

Yep, when condoms break it's obvious. If you think of the way a balloon looks after it's been popped, a broken condom is the same idea: they pretty much shred.

So there couldn't just be a hole in it?

You've got it Like Karyn said, any break is going to be very noticeable.

So if my boyfriend checked the condom after we had sex by filling it with water and nothing leaked then the condom worked?

I guess what I'm wondering is why if u use a condom for all genital to genital contact and after sex u check the condom good, how is it not 100% effective?

Effectiveness rates, for condoms and all other birth control methods, are calculated for a year of use, not for one instance of use. So when we say condoms are 98% effective with perfect use and 86% effective with typical use, we mean that in one year of use, 2% of people using condoms as directed, every time they have intercourse, will become pregnant and 14% who use them the way people do on average (taking into account improper storage, not using them every time they have intercourse, etc) will become pregnant. We don't have figures on how likely someone is to become pregnant from any one time they have sex; that's just not possible to calculate. But any time you use a condom as directed and it didn't visibly break or slip off, you can assume it did its job properly. If you aren't comfortable with that level of protection (from your questions here I get the feeling you may not be), you may want to look into using an additional form of birth control, and if you have questions about how to choose or obtain one we'd be happy to discuss that with you.

In terms of filling a condom with water, we don't recommend anyone do that. Condoms can actually form holes during this process that weren't there before, which will just cause extra worry. As Sam and Karyn said above, a hole will be noticeable - friction during sex would make even a small hole larger pretty quickly.