In a letter to a specialist journal, dermatologists in Nice said that over the past decade they had noted a rise in cases of a so-called poxvirus called Molluscum contagiosum, or MCV.
MCV causes painless, pearl-like nodules on the skin that usually disappear after a few months among people of normal health. It is sometimes seen on the face, arms and hands, but can spread through scratching or sexual contact.
The doctors reported on the case of 30 patients who over 14 months were treated at a private dermatology clinic in Nice for sexually-transmitted MCV.
Six of them were women and the rest were men; their average age was 29.
All but three of the patients had used pubic hair removal, with 70 percent using shaving.
All had MCV nodules on the pubis, abdomen or legs, while 10 also had other conditions such genital warts, bacterial skin infection or ingrown hairs.
Hair removal may cause "microtraumisms" to the surface of the skin, facilitating infection by the virus and other "minor" sexually transmitted infections, the doctors theorise.
The risk appears to be higher for shaving, but does not apply to laser treatment for hair removal.
"Pubic hair removal is a body modification for the sake of fashion, especially in young women and adolescents but also growing among men," according to the letter, published in the journal Sexually Transmitted Infections.
"The reasons for choosing genital hair removal remain unclear but may be linked with Internet-based pornography."