My girlfriend and I have been together eight years in a lesbian relationship. She has been diagnosed with cervical warts. What precautions should we take? I have not been diagnosed with this, but I've heard it can be transmitted to the throat through oral sex. Do I need to be tested? If so, what sort of doctor should I see, and what treatment would be involved? Also, what kind of problems can I develop in my throat and voice box?

S.M.

Genital warts are caused by certain strains of human papillomavirus (HPV). This group of viruses includes those that cause common warts of the hands and other areas. However, there are specific HPV serotypes (strains) that are much more likely to cause warts on the genitals and around the anus. In men, the penis is the most common area of involvement, while in women, the entrance to the vagina, as well as the labia minora and labia majora (the lips of the vulva, the female external genitalia), are the most common sites. The cervix (the entrance to the uterus), vagina, urethra (the tube that carries urine from the bladder) and anus can also be involved. The warts themselves look much like typical skin warts, but they are frequently much larger.

HPV is spread by direct contact, usually when there is minor abrasion and slight damage to the skin. In heterosexual intercourse, this factor explains the usual sites of involvement. Wart-like lesions can also be found anywhere in the oral cavity: the mouth and throat, as well as the palate, the tonsils and the inside part of the cheek. Recent studies have demonstrated that at least some of these warts are caused by the same HPV serotypes that cause genital warts. Often oral lesions will be found in a patient who already has genital warts. Some people with HPV infection of the oral cavity have no symptoms -- in fact, several studies have shown that many, if not most, healthy people will have evidence of oral infection with HPV, as measured by highly sensitive laboratory tests.

Certain strains of HPV are associated with cancer of the cervix, and the possible association between oral infection with these strains of HPV and the development of cancers of the mouth, head and neck is a concern. The actual risk of developing such cancers after an oral HPV infection is unknown, but it is probably low. Although the strains that have been associated with oral cancer are not usually the same strains that cause typical genital warts, more study is needed to assess the risk to partners of individuals with such warts.

Preventing HPV infection is no easy task. Although studies have shown that condoms decrease transmission of HPV during heterosexual intercourse, condoms do not eliminate all risk of the infection. Since direct contact commonly spreads the virus, abstinence from oral sex may be the only way to absolutely prevent the infection from being transmitted. But this may not be realistic for most people, and it is also possible that you are already infected. In most cases, however, there is not much to worry about. HPV-related warts in the oral cavity seem to be uncommon and oral cancers even more uncommon.