Not in the slightest bit surprised.
Sex education should consist of...well....education about sex!
And that includes information about the different diseases, risks, contraceptives, protection from disease, early symptoms of diseases and a whole host of other things. When this information is not actively provided to teenagers, it is unlikely that they will actually go out and research it themselves (teenagers already know everything don't forget!) and hence it is obvious that they are going to end up ilprepared.
__________________
|