About 43 percent of women experience sexual problems, according to another Boehringer Ingelheim study that examined their prevalence in a representative sample of 30,000 U.S. women. But only 12 percent found those problems "distressing," according to Dr. Jan Shifren, principal author of the PRESIDE study.
"As almost half the U.S. adult female population reported a sexual problem, sexual concerns should not be 'medicalized,'" she told ABCNews.com. As for those who were bothered by their lack of desire, "this group of women deserves effective treatment."
Many safe and effective options are available for treating women's sexual problems, typically addressing the underlying cause, which can be fatigue, stress, relationship conflict, depression or antidepressant medication.
"If an effective and safe medication is identified, it should be available to women, but given potential risks and side effects, drug therapy always should be considered a last resort," said Shifren, who is director of the Menopause Program in the Massachusetts General Hospital Department of Obstetrics and Gynecology.
"Women in good relationships who are physically and psychologically healthy are generally satisfied with their sex lives -- and you'll never find this in a medicine cabinet," she said.
Because flibanserin is an acting agent and not a hormone, like testosterone, Shifren, said she would want to see the safety data regarding mood effects and possibly blood pressure before prescribing the drug.
Beyond this study, the drug must show clinical improvement for women, effectively decreasing her level of distress about her sexuality, "for it to be effective," she said.
Problems with sexual desire are "a big deal," for women, according to Dr. Marie Savard, medical consultant to ABC News.
"We know the role of sex is so important to relationships," she said. "But for women it's unrealistic to think a pill is going to fix the impact of so many issues that women face."
Women have many reasons for lack of libido: stress, caregiving roles and lack of self-esteem -- " a big one," said Savard, and it's difficult to "label" women with a simple diagnosis like HSSD.
Still, because flibanserin works on the brain, "which is women's biggest sex organ," it might make sense that women would benefit from the drug.
"Unfortunately men's erectile dysfunction is simpler to fix," she said. "give a pill to increase blood flow or the equivalent of an on-off switch.
"Women are turned on by many competing different variable, hormones, timing, stress, sleep, self-esteem, and so our turn on is more like an airplane control panel -- lots of switches interacting to make things go."
Savard said she had "no doubt" the study increased episodes of sexual desire, but women must also side effects, especially because this drug is aimed at younger women.
"Do women really want to have to take a pill every day?" she asked. "It's kind of like treating with a gunshot approach. It's better that women understand what her individual cause is, like self esteem, which is the biggest."
Flibanserin has shown positive effects with a strong safety profile, according to Dr. André T. Guay, director for the Center for Sexual Function at the Lahey Clinic in Boston, who served as a medical consultant on the trials.