Ask this question: "Do you think reducing the number of abortions is important enough that men and women should be encouraged to alter, control or even discourage their sexual behaviors and desires to achieve that goal?"
This is a radioactive question for many people, because sex is supposed to be sacrosanct. Nothing can infringe on those acts or desires if they're consensual (at least while the crazier feminists are just barely restrained). And in our culture, answering affirmatively to this question is pretty well sufficient to separate one from the
Catholics may object that a possible answer to my question is 'Use contraception!', so there's a loophole. In this case, I think it's a positive byproduct of this question. There's an intellectual payoff for the concession that encouraging contraception use is yet another form of control over sexual behavior.