Reduced risk of sexual injuries in circumcised males

Yet another piggyback study using data from the HIV RCTs has been published. In this newly published study, using data gathered as part of the Kenyan trial, Mehta et al. report reduced risk of "penile coital injuries".

The authors report:

At baseline 1,775 (64.4%) men reported any coital injury including 1,313 (47.6%) soreness, 1,328 (48.2%) scratches, abrasions or cuts and 461 (16.7%) bleeding. On multivariable analysis coital injury risk was lower for circumcised than for uncircumcised men with soreness (OR 0.71, 95% CI 0.64-0.80), scratches/abrasions/cuts (OR 0.52, 95% CI 0.46-0.59), bleeding (OR 0.62, 95% CI 0.51-0.75) and any coital injury (OR 0.61, 95% CI 0.54-0.68).

So, these injuries — while minor — are fairly common and disproportionately affect uncircumcised males.

The authors suggest that this may affect the risk of HIV acquisition. This seems perfectly plausible, though it would be a mistake, I believe, to say that it is "the" mechanism by which circumcision protects against HIV. What's becoming clear, I think, is that circumcision protects against HIV through multiple mechansisms acting simultaneously.

I wonder, though, whether these findings might partly explain the fact that several studies have found that dyspareunia (painful intercourse) is more common among uncircumcised males?