Yes Euphemism I was being actually stupid as the WTS is in their publictions making such statements. They have made it more then once.
Watchtower May 15 1970, p. 315 Avoiding the Snare of Homosexuality ***
(see also Watchtower October 1 1970, p. 604)
Helpful in this regard, then, is appreciating the fact that autoeroticism or masturbation is no mere innocent pastime but rather a practice that can lead to homosexual acts . How so? In that self-induced masturbation may make it easier and more tempting for one to engage in mutual masturbation, which is a form of homosexuality. Sincerely striving against this practice will go far to protect a youth.
Watchtower 1973 Sept 15 pp.564-5 Breaking Free of Self-Abuse-Why? How?
The habitual practice cripples his social and emotional development, hinders his attaining a healthful outlook and attitude toward the other sex and toward people in general. It can 'turn the person inward' upon himself, making him introverted. Or it can, and frequently does, lead into homosexuality , in which the person, not satisfied with his lonely sexual activity, seeks a partner for mutual sex play.
Watchtower 1976 February 15 pp.122-3 You Must Be Holy Because Jehovah Is Holy
Likewise, unclean practices, such as masturbation, which can be a steppingstone to homosexuality , have been dealt with in a serious, yet understanding, way, to help individuals keep clean and pure in Jehovah's eyes.
Your Youth (1976) p.39 Chapter 5 Masturbation and Homosexuality
In fact, masturbation can lead into homosexuality..............
This happens much more frequently than you may realize. Contrary to what many persons think, homosexuals are not born that way, but their homosexual behavior is learned.
Seedy
All Quotes taken from http://quotes.jehovahswitnesses.com/masturbation.htm