The findings about Pap tests suggest that young lesbian and bisexual women are not monitoring their sexual health as much as their heterosexual counterparts and could be at risk of developing cervical cancer. These women “report having sex at a younger age and with more people,” said lead study author Brittany Charlton, a graduate student in epidemiology at the Harvard School of Public Health. “That could certainly put them at risk. It’s really important that they be screened.”

Lesbians, who made up abouut 1 percent of the women surveyed, were less likely to have gotten a Pap test, which detects the presence of a sexually transmitted virus that can cause cervical cancer and other medical problems. In the previous year, 70 percent had undergone screening, compared with 88 percent of heterosexual women.

Twenty-two percent of bisexual women said they had a previous diagnosis of a sexually transmitted disease, in comparison with 11 percent of those who were heterosexual and 8 percent of lesbians.

Women who have sex with other women are at lower risk of getting sexually transmitted diseases than are women who have sex with men, although some of the diseases can spread between women. There is a complicating factor to this picture: Young women who are not heterosexual most likely have still had sex with men at some point in their lives. Research suggests that about three-quarters of sexually active lesbian adolescents have had sex with men; the number is 96 percent among bisexuals.

In fact, research has shown that women are at risk of transmitting human papillomavirus − which can cause cervical cancer − to each other through sex, said Devika Singh. 'There continues to be a lack of general awareness on the part of many health care providers on what defines sex between women and what risks may be associated with sexual practices between women,” Singh said.

"Regardless of their sexual orientation, women need to find a doctor or nurse practitioner they trust and get checked,” Charlton said. “That’s important to their life overall. And medical professionals need to be sure to screen all their patients regardless of their sexual orientation.”