I think he is talking about increased condom usage relating to the fear of getting HIV having an indirect effect on the number of accidental pregnancies.
This just reminds me of an old experiment that tried to use artificial group selection to make Tribolium insects ( http://www.pnas.org/cgi/reprint/73/12/4604.pdf ) restrain their breeding, when instead they just ended up cannibalizing others' eggs (focusing on the females). People say HIV is a good excuse to fear having sex at all, conspiracies about the Vatican suggest it was developed for such a purpose, but nope, people just use condoms. Humans are as silly and fascinating as all the other life around here.
