You have a point there, but young couples never think, they just do it, which I find rather dumb. Real Relationships actually do think about it, but sometimes it's never been brought to their attention. In the UK, there's lot's of teenagers having Kids and their like 15-16 and they usually don't care for their kids which is just wrong. But it was their fault for having sex.
It's usually what lot's of people do nowadays from what I see. It sometimes comes on news, and usually people question to them "If you didn't want a baby, why did you have sex?" and that usually makes the young mother feel like she got owned, because she can't even think of a good reason, and can't justify it either. So they knew it, and they have to face it.
It's right not to be a couple at a young age, but it really affects them, not us. So we can't control them. But usually young couples have sex right after they've drunk lots of alcohol, that's usually the case But from what I see, 15-16 year old's are mostly aimed at, so why are even drinking alcoholic beverages? But there's many reasons for why they have sex.