Childhood sexual abuse (CSA) is a strong predictor of adverse physical and mental health outcomes (Koenig, Doll, O’Leary, & Pequegnat, 2004; Lalor & McElvaney, 2010). Recent research has found that CSA is reported more frequently by lesbians than by heterosexual women (Austin et al., 2008;Balsam, Rothblum, & Beauchaine, 2005; Stoddard, Dibble, & Fineman, 2009). Possible reasons for lesbians’ higher CSA rates include childhood maltreatment (e.g., physical and sexual abuse) because of gender atypical behavior (Tjaden, Thoennes, & Allison, 1999), and involvement in behaviors (e.g., substance abuse, running away from home) that increase risks of sexual victimization, following family and peer rejection due to same-gender orientation (Ryan, Huebner, Diaz, & Sanchez, 2009).The study itself finds that lesbians were far more likely to be victimized as children than heterosexual women, and the severity of that abuse was far more severe. The odds ratio in Table 1 shows how much more common the abuse of the lesbians had been than the heterosexuals -- 3.07 times for any type of CSA, and the severity measures are in nearly every category more severe for the lesbians than for the heterosexual women.
The paper does not even consider the possibility that the severity of the abuse (and that is a horrendous set of data above) might explain the adult sexual orientation; instead, the adult sexual orientation must be the cause of the abuse!