Oral sex is "theoretically" a sincerely low risk; however, the risk is so close to zero that it cannot be calculated. This doesn't mean to go enjoy oral sex with someone bleeding from the gums while massaging your genitals with a cheese grater, but you shouldn't be too concerned. If you would like to know the statistics of HIV/AIDS based on gender, you can easily go Google "HIV Statistics." I am a male and have openly admitted to multiple doctor's before that I had received unprotected oral sex. They've never recommended that I get an HIV test.