Plenty of readers, of course, will have very strong opinions about teenagers having sex. They don’t care. They are doing it, and will likely keep doing it even with years of abstinence-only messages thrown at them. Study after study has shown such programs to be ineffective. In fact, not only do they fail to prevent teen pregnancy or the spread of STDs, but, write the authors of one paper in the journal PloS One, they may “actually be contributing to the high teenage pregnancy rates in the U.S.” Such programs are also immoral, write the authors of another paper, because they withhold and distort information about sex and the risks of STDs, including HIV, that could save lives.