My work is often criticised because it objectifies women. From my very first paintings, it was always intended to do so. All woman are conscious of when they first become objectified. It happens at puberty when our physicality begins to come into focus. And as soon as we are in our teens, we encounter problems with men who only care about the possibility of bedding us. Over and over, older women told me I should think it flattering, instead of inappropriate or abusive.We're so used to being objectified we don't really know how to look at ourselves any other way, especially sexually. In every culture and subculture, the physical ideals for women are far more codified and rigid than those for men. I try not to reduce women to either sex toys or trophies (at least, not without some irony) in my work but I do try to explore women's real desires and fantasies, starting with my own. My generation of women is the first to be able to speak openly about our sexual experience, and to experiment outside the conventions of it, without being cast out of society. I objectify women in my work in the same way that I think young women now objectify themselves – as an attempt to harness and reverse the power that men have had over us. I'm also trying to reflect society's values back on itself in the hope that it illuminates the darker aspects of its sexual mores.If my recent drawings of headless schoolgirls fingering their pussies look like some teenage fantasy, it's because they are – mine, from when I was in my teens. Women's sexuality is often denied. Just as often, we're denied a chance to express it. My drawings trace a younger reality for me: what I did alone, shyly, feeling partly silly, partly ashamed, and yet totally turned on by whatever fantasy was inside my head. The developing sexuality of young girls, starting with fumbling, self-conscious masturbation, isn't accepted as matter-of-factly as that of young boys'. And if women are still ashamed of their bodies and desires, what chance do they have to get beyond society's over-amplified projection of both to gain a real understanding of themselves? Without acknowledging and expressing the needs and urges deep within us, we'll continue to allow men to do it for us – and to expect us to live up to their misplaced, totally mistaken ideas.