Background: An increasing number of persons around the world are receiving the diagnosis of gender incongruence, and most of them are in their reproductive years. Safe contraception and fertility preservation are important issues for counseling.
Methods: This review is based on pertinent publications retrieved by a systematic search in the PubMed and Web of Science databases, employing the search terms "fertility," "contraception," "transgender," "gender-affirming hormone therapy" (GAHT), "ovarian reserve," and "testicular tissue." 908 studies were included, 26 of which entered the final analysis.
Results: Most of the available studies on fertility in trans persons undergoing GAHT reveal a marked effect on spermatogenesis, but no impairment of ovarian reserve. No studies are available on trans women; the data show that 59-87% of trans men use contraceptives, often mainly in order to suppress menstrual bleeding. Fertility preservation measures are mainly used by trans women.
Conclusion: GAHT mainly impairs spermatogenesis; thus, counseling on fertility preservation should always be given before GAHT. More than 80% of trans men use contraceptives, mainly for their other effects such as suppression of menstrual bleeding. GAHT is not in itself a reliable method of contraception, and persons about to undergo GAHT should always receive contraceptive counseling.