Here's a reference you might find informative from What Causes Homosexual Desire and Can It Be Changed?
4) Early homosexual experiences influence adult patterns of behavior
In the 1980s, scholars (12) examined the early Kinsey data to determine whether or not childhood sexual experiences predicted adult behavior. The results were significant: Homosexual experience in the early year, particularly if it was one's first sexual experience - was a strong predictor of adult homosexual behavior, both for males and females. A similar pattern appeared in the 1970 Kinsey Institute (4) study: there was a strong relationship between those whose first experience was homosexual and those who practiced homosexuality in later life. In the FRI study (5) two-thirds of the boys whose first experience was homosexual engaged in homosexual behavior as adults; 95% of those whose first experience was heterosexual were likewise heterosexual in their adult behavior. A similarly progressive pattern of sexual behavior was reported for females.