The thing about shotgun weddings...

It's often said that the hardcore social conservatives aren't really concerned about abortion; otherwise they'd support safe-sex education, contraception, and other things that actually reduce the demand for abortions. More broadly, what they want to do is preserve the plank in their arbitrary morality system which says sex outside of approved conditions is unethical. But the anti-sex league also realizes that modern developments have sharply marginalized, if not eliminated, actual material consequences from unsanctioned sex, which is why they furiously wave their hands at harmless preventative measures like condom distribution. To preserve their antiquated vision of morality, they have to ensure that the erstwhile punishment for wanton sex remains active, however artificially.

What this means, of course, is that the kids born to these teenage mothers have to live with the fact that they were meant to be punishment for their parents' indiscretion. That seems like an awful lot to hang on a kid, since most people tend to resent their punishment. I'm not a psychologist, but I can't see how that's a positive situation.