My attraction is more physical, emotional, and sensual than exclusively sexual. Although there continues to be controversy and uncertainty as to the genesis of the variety of human sexual orientations, there is no scientific evidence that abnormal parenting, sexual abuse, or other adverse life events influence sexual orientation. I came out as gay in my early 20s, then dated men as it seemed much easier and hid my attraction to women for most of my 20s. But I think my ideas and feelings about my sexuality have been constantly changing since I was aware of having any sexuality. I started doing this in my early twenties, just after leaving university. The default developmental pathway for a human fetus being female, the Y chromosome is what induces the changes necessary to shift to the male developmental pathway. However, research suggests that this may be of immunological origin, caused by a maternal immune reaction against a substance crucial to male fetal development during pregnancy, which becomes increasingly likely after every male gestation. Despite seven categories being able to provide a more accurate description of sexual orientation than a dichotomous scale, it is still difficult to determine which category individuals should be assigned to. I decided on my sexuality age 18 after many years of torturing myself for not falling cleanly on one side of the fence or the other. From here, the anti-male bodies would then cross the blood—brain barrier of the developing fetal brain, altering sex-dimorphic brain structures relative to sexual orientation, causing the exposed son to be more attracted to men over women. In Freud's view, this was true anatomically and therefore also psychologically, with sexual attraction to both sexes being one part of this psychological bisexuality. Freud believed that in the course of sexual development the masculine side would normally become dominant in men and the feminine side in women, but that as adults everyone still has desires derived from both the masculine and the feminine sides of their natures. In the early nineties, living in the shadow of the Aids epidemic, educated under the restrictions of Section 28 and before the age of the internet how was I to know any better other than the courage of my own convictions? Assessing sexual attraction will yield the greatest prevalence of homosexuality in a population whereby the proportion of individuals indicating they are same sex attracted is two to three times greater than the proportion reporting same sex behavior or identify as gay, lesbian, or bisexual.