A new study suggests most women who are sexually active when they reach middle age will remain so as they grow older, even if they are diagnosed with a sexual dysfunction.

"There's this popular public perception that as women age, sex becomes unimportant, and that women just stop having sex as they get older," lead author Dr. Holly Thomas told Reuters Health. "From our study, it looks like most women continue to have sex during midlife."

"It may be detrimental to label a woman as sexually dysfunctional," Thomas said.

Researchers looked at 354 middle-aged and older who were sexually active at the time of the test; they were tested again four years later. Over 85 percent of the women who reported being sexually active remained so over the course of the study that were between the ages of 48 and 73.

"I think there is a cultural bias," Thomas, told the Huffington Post. "Culture tells us that this (sex) is something older women shouldn't be interested in."

The doctors employed the Female Sexual Function Index; which consists of 19 questions concerning "arousal, orgasm, vaginal lubrication and pain during intercourse," Reuters reported.

The women who remained sexually active scored an average of 22.3 on the index, which is below the cutoff for sexual dysfunction at 26.55. The team found the index failed to accurately predict if the women did or did not remain sexually active. This suggests women are being wrongly labeled as sexually dysfunctional.

"[The index's] focus on intercourse may not accurately reflect what constitutes satisfying sex in this population, yielding falsely low scores," Thomas wrote, Reuters reported.

More important factors in sexual function are believed to be "race, weight, relationship status and how important women deemed sex," Reuters reported.

The team found women who rated sex as "important" were three times more likely to remain sexually active than those who did not.

"We've seen from other research that a healthy sex life is a predictor of longevity," Thomas said. "So understanding sex might have broader implications for overall health."