Stability After Legal Gender Change Among Adults With Gender Dysphoria.

Importance: The number of people seeking treatment for gender dysphoria (GD) has risen in recent decades, yet data remain limited for understanding cases of detransition (ie, the reversal of social, medical, or legal transition). Legal gender change in national registers poses an opportunity to examine legal gender reversals, which may reflect an aspect of the detransition process, while also informing an understanding of the stability after a legal gender change.

Objective: To determine the probability of obtaining a legal gender change and its stability over time among people diagnosed with GD in Sweden during a 10-year study period.

Design, setting, and participants: In this population cohort study using data from Swedish national registers from January 1, 2013, to December 31, 2023, individuals who received their first International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10), diagnosis code for GD during the study period were included. While participants may have received a GD ICD-10 code as youths, legal gender changes only occurred for adults (aged ≥18 years) based on legal requirements during the time of data collection.

Exposure: Gender dysphoria.

Main outcomes and measures: Legal gender change and its stability, that is, absence of legal gender reversal, as reported in the registry. Kaplan-Meier survival analysis was used to determine the probability of legal gender change and its stability during a 10-year study period.

Results: A total of 7293 people with a GD diagnosis were included (36 025 person-years). Approximately one-third of the sample (n = 2467) obtained a legal gender change during the study period. The probability of legal gender change at 10 years following diagnosis was 58.3% (95% CI, 56.2%-60.4%). Twenty-one cases of legal gender reversal were identified. The probability of legal gender stability at 10 years following the initial change was 97.7% (95% CI, 96.3%-99.2%), with no differences by sex assigned at birth for either outcome.

Conclusions and relevance: In this cohort study using national population registry data, a significant proportion of participants with GD in Sweden obtained legal gender change within 10 years of follow-up. Despite significant growth of the population with GD, the probability of legal gender stability during the 10-year study period was high, at almost 98%. These results highlight that legal gender reversal was an infrequent occurrence in a national sample.