Being the strong Christian that I am I would always tell people that I was waiting for religion purposes. However I started asking myself is that the only reason I am waiting, and it didn't take long for me to realize it wasn't.
Besides religion the only other good reason I could think of is fear. For example I have a friend who lost her virginity to her serious boyfriend at the time and then a week later they broke, because of that she went into a self blaming depression and didn't talk to me or other friends for almost 2 months. I have another friend who has had many partners and she too has gone through depressive stages and is in therapy for emotion distress and other troubles, because she giving love but not receiving it . Long story short, I don't want to go through something like they did, and I have many other examples of how pre-material sex has both physically, emotionally and mentally harmed people close to me.
So I decided to wait until marriage because I want to be with some who loves me for me and not just my body. Plus i also think it will build a stronger relationship, because during the dating stage you are getting to know the person on a personal level, their likes, dislikes hobbies, etc, and I feel that all of that is the basis of a strong and healthy relationship and hopefully marriage.