sex behaviors among a sample of men (n=1,299) and women (n=1,919) compared to anal intercourse experience and found that 51% of men and 43% of women had participated in at least one act of oral–anal sex, manual–anal sex, or anal sex toy use. The report states the majority of men (n=631) and women (n=856) who reported heterosexual anal intercourse in the past 12 months were in exclusive, monogamous relationships: 69% and 73%, respectively. The review added that because "relatively little attention [is] given to anal intercourse and other anal sexual behaviors between heterosexual partners", this means that it is "quite rare" to have research "that specifically differentiates the anus as a sexual organ or addresses anal sexual function or dysfunction as legitimate topics. As a result, we do not know the extent to which anal intercourse differs qualitatively from coitus." According to a 2010 study from the National Survey of Sexual Health and Behavior (NSSHB) that was authored by Debby Herbenick et al., although anal intercourse is reported by fewer women than other partnered sex behaviors, partnered women in the age groups between 18 and 49 are significantly more likely to report having anal sex in the past 90 days. Women engaged in anal intercourse less commonly than men. Vaginal intercourse was practiced more than insertive anal intercourse among men, but 13% to 15% of men aged 25 to 49 practiced insertive anal intercourse. With regard to adolescents, limited data also exists. This may be because of the taboo nature of anal sex and that teenagers and caregivers subsequently avoid talking to one another about the topic. It is also common for subject review panels and schools to avoid the subject. A 2000 study found that 22.9% of college students who self-identified as non-virgins had anal sex. They used condoms during anal sex 20.9% of the time as compared with 42.9% of the time with vaginal intercourse. Anal sex being more common among heterosexuals today than it was previously has been linked to the increase in consumption of anal pornography among men, especially among those who view it on a regular basis. Seidman et al. argued that "cheap, accessible and, especially, interactive media have enabled many more people to produce as well as consume pornography", and that this modern way of producing pornography, in addition to the buttocks and anus having become more eroticized, has led to a significant interest