With the common practice of oral sex, it is always a issue of what to do when you get semen in the mouth.
The safest thing to do with semen in your mouth is to swallow it or spit it out. When you swallow it the enzymes and acids in your stomach will quickly destroy any viruses and bacteria.
When you spit it out, use a mouthwash to remove any lingering semen. Don’t brush your teeth before or after oral sex. The brushing can cause slight bleeding of your gums leaving them open to infection from HIV.
Semen does not have any toxins and poisons.
When you swallow semen, Semen and sperm go down into your stomach, where they are digested with all your other food. There is no passage connecting your stomach to your ovaries. You can not get pregnant from swallowing sperm.
If the donor has no STDs, it is perfectly safe. If you plan to have a baby with the man in question, it can also lower the chance of miscarriage. By having your body recognize the antigens in the mans semen you can reduce the possibility of an inappropriate immune response.
In case the person is infected, you can catch diseases like gonorrhea, syphilis, herpes and chlamydia. HIV virus is contained in body fluids, like semen, but it has to get into your blood through your bleeding gums or damaged teeth. If your mouth is strong and your gums are firm, then you can swallow the HIV virus without any trouble.