I'm not sure I'm convinced of a causal relationship here but I think the correlation is very interesting indeed:
Why Abstinence-Only Sex Ed Makes Kids Into Bullies
Here's how the article gets started:
"Abstinence-only education creates a petri dish for bullying in schools. There is always a lot of back and forth about the efficacy of these programs, and I fall on the side that they demonstrably fail to reduce teen pregnancy, the rate of incidence of teen sex, or the transmission of sexutally transmitted infections (STIs) (all you have to do is look at Texas). In addition, however, I believe that the heyday of our federal investment in abstinence-only programs had a terrible collateral effect -- namely, kids who were "educated" in this way were more likely to bully and harass because they learned, in ways integral to abstinence provisions, outdated "traditional" ideas about gender and sexuality. Even kids whose parents talked to them at home, about contraception or healthy sex, were taught gendered rules and more and more of them appear to have enforced those rules to great harm."