IMO Creating a taboo of any kind, incites natural rebellion. Just like my naughty cats who always do whatever it is that they know annoys me most in order to get my attention...

With girls, I think that a very gentle "it's here if you need it" approach is best, along with all the essential information about how pregnancy can cause major upheavals etc.

But IMO, give them fast easy access to the child prevention technology, before they even need preaching to, would be the most pragmatic solution to an awful lot of buggered up lives...