Childhood and adolescent sexual behaviors predict adult sexual orientations

Anonymous retrospective data were provided by 3,443 adult participants via computer-assisted self-interview. This was the first study focused on determinants of adult sexual orientation to adjust for the effects of same-sex sibling incest. Five measures of adult sexual orientations (ASOs) provided evidence consistent with the theory that ASOs result from early sex-specific romantic attachment, conditioning caused by early sexual experiences with partners, and other experiences, such as early masturbation using human images, acting synergistically with critical period learning, and sexual imprinting. Early same-sex crushes were the most powerful predictor of ASOs, and they also increased the likelihood of engaging in early same-sex partnered and masturbation behaviors. Incestuous experiences with same-sex siblings affected the ASOs of the incest participants. And, lesbian, gay, and bisexual participants tended to have an earlier onset of puberty than heterosexual controls within sexes. However, statistical analyses showed that the incest and puberty effects were mathematically explained by the participant’s early sexual experiences with partners and other experiences such as masturbation using human images. Early same-sex crushes were predicted by nuclear family variables implying that same-sex crushes were more likely when the opposite-sex parent modeled an unsatisfactory heterosexual romantic partner