To include or not to include. Is that really the question?
Well, it depends doesn't it? A big reason books are banned is for sexual content. But teens want to read about something relevant to their lives. What is more relevant than sex? Having it, not having it, it occupies a good space of brain time in your average teenager. And if they aren't having it, don't want to have it, won't have it in their teen years, they are, at the very least, confronted with it every day by peers, ads, TV, magazines, etc.
So these aren't necessarily real life situations. If a teen has sex, she has to deal with the possibilities of STDs, pregnancy, or personal or social humiliation. So what's the point of including sexual situations in fantasy novels? A teen doesn't need a "How to Survive Having Sex with a Vampire" handbook.
What's the point? It gets the teen thinking. It gets the teen out of her own head for a moment. It allows the teen to project. And it allows the teen to sympathize with the main character in her own plight. She will recognize in the main character her own emotions, confusion, and dilemmas.
Twenty Boy Summer by Sarah Ockler and Thirteen Reasons Why by Jay Asher are two contemporary YA that both deal, at least in part, with sex and the consequences. I won't get into them much here, but know that I loved both of these books. They handle the dilemma of teen sex so well, both in vastly different ways, that, had they landed on my desk, I would have scooped them up (not for the sex dilemma alone, but the incorporation was very well done).
So, the question isn't really to include of not to include. It's more about the appropriateness to your story. Don't include sex for the sake of having it in there. If there is no point, no lesson, no conclusion to draw from the scene, then it isn't helping. It might be harming your novel.
The following links talk more in depth about sex and romance in YA novels--probably better than I could.
Romance from Justine Dell.
Edgy YA from Query Tracker.
And the book I'm looking forward to reading with this topic in mind is The Duff by Kody Keplinger. (Click for a great review.)
So the questions you might want to ask yourself are:
How much is too much? How can the author gage what will be acceptable for teens to read? How does the author decide what the teen can identify with? When is it worth taking the risk of adding sexual material, and just leaving it out in favor of something else? Is it allowable to be explicit in YA, or is it common courtesy to gloss over the details?
So, dear readers, your turn. Enlighten me to your thoughts. Happy writing.