Why Are Some People Homosexual or Bisexual? Most scientists today agree that sexual orientation (including homosexuality and bisexuality) is the result of a combination of environmental, emotional, hormonal, and biological factors. In other words, there are many factors that contribute to a person's sexual orientation, and the factors may be different for different people.
However, homosexuality and bisexuality are not caused by the way a child was reared by his or her parents, or by having a sexual experience with someone of the same sex when the person was young. Also, being homosexual or bisexual does not mean the person is mentally ill or abnormal in some way, although there may be social problems.
