suggested that gender differences in sexual fantasies have actually narrowed over time, and may continue to do so, for example with regard to variety of sexual fantasy and the amount of fantasizing reported by each of the sexes. Age The age of first experiencing a sexual fantasy has also been found to differ between the sexes. Males are likely to report this at a younger age, typically between the years of 11 and 13, and describe these as being more explicit in content. Themes that were common to both genders regarding first sexual fantasies included sex with celebrities (such as movie stars), and also teachers. It has been noted that sexual fantasy preferences of the two genders also change as a function of age. For instance, younger men have been found to endorse more fantasies with multiple partners, a trend which declines with age, whilst homosexual fantasies increase slightly. Meanwhile, for women, fantasies with strangers and same-sex partners remain relatively stable across the lifespan. Paraphilic sexual fantasies Sex differences have also been found with regard to paraphilic fantasies (i.e. those which are considered to be atypical). Examples of paraphilic sexual fantasies include incest, voyeurism, transvestic fetishism, sex with animals (see zoophilia), and pedophilia. One study reported that over 60% of men admitted to a sexual fantasy involving intercourse with an underage partner, and 33% of males reported rape fantasies. Along with other sexual fantasies, it is thought that the age of occurrence for paraphilic sexual fantasies is usually before 18 years, although this has been found to vary according to the specific fantasy at hand. Unusual sexual fantasies are more common in men, with fantasies of urinating on their sexual partner and being urinated on being significantly higher among males. The Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV) states that paraphilias are rarely diagnosed in women, with the exception of sexual masochism. Furthermore, sexual arousal has been found to be greater in men than in women when asked to entertain the thought of engaging in paraphilic sexual activity. It may, however, be the case that paraphilias are reported less often in women because they are under-researched in women. Paraphilic sexual fantasies in females include sexual sadism, exhibitionism, and pedophilia. Execution of sexual fantasies Sexual fantasies may be more likely to be executed in contemporary society due to more liberalized attitudes towards the previously taboo topic of sex,