So, I'm not sure that I would still classify myself as a Christian or not, but either way.
When I was in my mid teens, I definitely had a hang-up about sex. No one had ever taught me anything (through my church groups or otherwise) about what sex is other than "BAD" so not only was I ashamed of thinking about it, I was completely uneducated. And I was too ashamed to ask anything. Now that I've gotten a bit older, I understand what it is; I get that sex is a good thing, it's not this dirty unmentionable that my elders mad made me think (whether they did that on purpose or not, I don't know). But I also know that away from the Christian setting, my biological family was pretty screwed up and their sexual mistakes are what led to it. Even now, I'm pretty scared of men. I don't think sex is a bad thing; quite the contrary I think it's a wonderful thing, and even though I've made (what I consider to be) mistakes in regards to it, I think it's one of those things that is so wonderful that I only WANT to share it with one person. That could be more based on my personal experience that my childhood faith.