Deep French kissing (DFK) is a passionate style of open-mouthed kissing where the couple sticks their tongues down each other’s throats, instead of keeping them inside one another's mouths. The spread of sexually transmitted infections is much greater with deep French kissing than with regular French kissing.
Many couples find deep French kissing to be arousing and a good way to feel closer to one another. It is often an element of foreplay. Sex workers offering the girlfriend or boyfriend experience also typically offer deep French kissing as one of their services.
Despite the perks of deep French kissing, this practice does carry some risks. Just like regular French kissing, if one of the kissers has a cold sore, herpes can be spread. Deep French kissing can also spread additional sexually transmitted infections, including gonorrhea, syphilis, and hepatitis B.
Generally, there is no risk of spreading HIV during deep French kissing. This virus is transferred through blood rather than saliva. If the kissers have bleeding gums or open sores, however, there may be some risk.
