Teen BJs & Vajayjays: A Study

A new analysis of the sexual practices of 2,271 15- to 19-year-olds challenges the widespread perception that today's teens are substituting oral sex for intercourse to preserve their virginity.
"...it looks like once you start having vaginal sex, then you start oral sex also, but it could also be true that you start off having oral sex and sometime after start having vaginal sex," a spokesperson says. "We don't know which one came first."
more HERE

...wow! it's the whole 'chicken & egg' thing...