I in general agree with Tom about Christian religious dogma and sex. Yes the risks of STDs are probably overstated if you take precautions, but most studies show that most people don't and that is particularly true for young people.
However, to my way of thinking the risk of unwanted pregnancy is the greatest risk and one that men just don't have to deal with. The worst that will happen to a guy is he has to take responsibility and pay 18 years of child support. Yes, again, both people should take precautions, but as Alex points out none of these methods are 100% safe and reliable. Yes, with precautions the risks are minimized and there is always the abortion option. But, a woman should never totally ignore those risks. Women can and still do die in child birth, rare though it may be. Men don't always take responsibilities as they should. Abortion has its own risks, both physical, emotional and some would say spiritual. Being a parent is a major life changing event. Doh! Being a single parent even more so. And for those of you men who are honorable enough to take care of your responsibilities, where is the guarantee that she will let you. Maybe you were just a sperm source for her and she may accept your child in her life, but not you.
Most of us probably think we are a little too old for that lecture, but a reminder never hurts.
Again, this is not a reason to avoid experiencing life, love and sex. Whether you wait until you marry or not, you are still experimenting with a relationship when you have sex. I agree with Tom, part of finding what you need, is trying it out and learning what does and doesn't work for you. But, I agree with Alex, women still need to be more prudent than men, because they are taking the greater risk.
I was debating about putting in this plug. WTH Now guys if you would just go after us older women, you wouldn't have to worry about the pregnancy risk.