Are condoms a good, reliable form of contraception?

Yes: When used properly each & every time, and assuming no breakage or slipping off, condoms are a good & reliable form of contraception. Not only that, condoms are only way to decrease risk of sexually transmitted infections, short of abstinence. But to be safe, we always recommend two forms of contraception, eg hormonal birth control (so you're in control) and condoms. And you can always say no.

If used perfectly: If used perfectly (every act of intercourse, no condoms breaking or slipped off, used correctly as described here: http://www.Wikihow.Com/use-a-condom) e by 100 couples, 2/100 will get pregnant over the course of 1 year. In typical use (which likely includes some times when condoms aren't used), 28/100 couples will get pregnant.