Hormone replacement therapy for transgender or gender variant individuals, also sometimes called cross-sex hormone therapy, is a form of hormone replacement therapy (HRT) in which sex hormones (namely androgens for trans men and estrogens for trans women) are administered for the purpose of synchronizing a person's secondary sexual characteristics with their gender identity. Some intersex people may also undergo HRT, either starting in childhood to confirm the sex they were assigned at birth, or later in order to align their sex with their gender identity.