Unveiling the Distinctive Landscape of Female-to-Male Transsexualism in Japan
Imagine a country where the typical patterns of transgender identity are turned upside down—where individuals assigned female at birth seeking gender transition outnumber their male-assigned counterparts by a significant margin. This isn't a theoretical scenario; it's the reality in Japan, where research has revealed fascinating distinctions in how gender identity disorder manifests across cultures.
FTM individuals outnumber MTF individuals by approximately 2:1 in Japan, contrasting with patterns in Western countries.
High rates of PCOS (32%) found among FTM individuals in Japan suggest potential biological factors.
The 2011 study "Distinctive features of female-to-male transsexualism and prevalence of gender identity disorder in Japan" uncovered this unexpected pattern, challenging long-held assumptions and opening new questions about the biological and cultural influences on gender identity.
This groundbreaking research not only documented a unique sex ratio among transgender Japanese people but also revealed startling health correlations, including high rates of polycystic ovary syndrome (PCOS) among female-to-male (FTM) individuals. These findings provide crucial insights into the complex interplay between biology, identity, and culture, offering a compelling case study in how gender identity manifests differently across populations.
Before exploring the Japanese context, it's essential to understand some key terminology. Gender dysphoria refers to the psychological distress that results from an incongruence between one's experienced gender and one's sex assigned at birth2 .
One's internal, deeply held sense of gender, which may or may not align with sex assigned at birth.
Distinct from gender identity; refers to emotional, romantic, or sexual attraction to others.
It's crucial to distinguish this from being transgender itself—the American Psychiatric Association notes that while many transgender people experience gender dysphoria at some point, not all do, and the diagnosis specifically focuses on the distress rather than the identity2 .
The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) outlines specific criteria for gender dysphoria, which include a marked incongruence between one's experienced/expressed gender and assigned gender, lasting at least six months, and manifested through various symptoms such as a strong desire to be of another gender, a strong dislike of one's sexual anatomy, or a strong desire for the physical sex characteristics of another gender5 .
The 2011 study published in the Journal of Sexual Medicine revealed startling findings about the transgender population in Japan. Through careful analysis of 104 male-to-female (MTF) and 238 female-to-male (FTM) Japanese patients, researchers found prevalence rates of approximately 3.97 per 100,000 people for MTF individuals and 8.20 per 100,000 for FTM individuals3 . This 1:2 ratio stands in stark contrast to patterns observed in many Western countries, where MTF individuals often equal or outnumber FTM individuals.
More recent research using different methodology has suggested even higher prevalence rates. A 2022 population-based survey using the Utrecht Gender Dysphoria Scale found that when using a broader definition, gender dysphoria affected 0.87% of individuals assigned male at birth and 1.1% of individuals assigned female at birth in Japan7 —significantly higher than earlier clinic-based estimates.
Beyond demographic patterns, the Japanese study uncovered significant health correlations among FTM individuals. The research team conducted thorough medical assessments, including transvaginal or transrectal ultrasonography and measurement of serum hormone levels and insulin resistance indexes3 .
Diagnosed with PCOS
Insulin Resistance
Hypoadiponectinemia
Their findings were striking: among the 128 FTM patients who had not previously taken hormones (the "untreated group"), 32.0% were diagnosed with polycystic ovary syndrome (PCOS), 30.1% showed insulin resistance, and 31.1% had hypoadiponectinemia (low levels of a hormone involved in regulating glucose levels)3 .
| Health Condition | Prevalence | Description | Potential Implications |
|---|---|---|---|
| Polycystic Ovary Syndrome (PCOS) | 32.0% | Hormonal imbalance often involving elevated androgens | Possible intersection with gender identity; requires gynecological care |
| Insulin Resistance | 30.1% | Reduced response to the hormone insulin | Increased risk for type 2 diabetes; requires monitoring |
| Hypoadiponectinemia | 31.1% | Low levels of adiponectin hormone | Associated with insulin resistance and metabolic issues |
PCOS is a condition characterized by hormonal imbalance that often includes elevated androgen levels, irregular menstrual periods, and sometimes cysts on the ovaries. The high prevalence of PCOS among FTM Japanese individuals suggests a potential biological factor that might intersect with gender identity development, though the exact nature of this relationship remains unclear.
Understanding the healthcare context for transgender individuals in Japan requires examining both their surgical desires and the barriers they face. A 2025 prospective, multicenter survey of 107 individuals with gender incongruence in Japan found that 69% desired gender-affirming surgery (GAS), while 29% did not, and 2% were undecided1 .
The reasons for desiring surgery were varied: 62% expressed positive feelings about changing their legal gender, while 24% felt it was unavoidable for this purpose. Other significant factors included the need for mental stability (56%), reducing gender dysphoria (54%), and becoming one's "true self" (37%)1 .
However, substantial barriers prevent many from accessing surgical care. The most frequently cited reason for not wanting GAS was difficulty securing funds for surgery (58%), followed by resistance to gonadectomy (41%)1 . These financial challenges persist despite Japan's healthcare system covering some procedures.
One particularly innovative study from 2017 used eye-tracking technology to investigate whether the sexual interest patterns of FTM transsexual persons resembled those of biological men8 . This research addressed a fundamental question about the relationship between gender identity and sexual response patterns.
The study included 15 biological men and 13 FTM transsexual subjects who had not yet undergone gender-affirming surgery. Participants viewed three different sexual videos while their eye movements and gaze patterns were meticulously tracked using specialized equipment.
The videos included:
The findings revealed statistically significant differences in viewing patterns between men and FTM transsexual subjects for the first two videos.
Perhaps most strikingly, FTM participants spent 8.35% of their viewing time looking at the body of the male actor in clip 2, compared to only 0.03% for biological men—a dramatic difference that suggests fundamentally different patterns of sexual interest.
| Research Tool | Function | Application in Gender Identity Research |
|---|---|---|
| Utrecht Gender Dysphoria Scale (UGDS) | Standardized assessment tool for gender dysphoria | Measuring severity of gender dysphoria in population studies7 |
| Eye-Tracking Technology | Precisely measures where and how long subjects look at visual stimuli | Investigating patterns of sexual interest without relying on self-report8 |
| Ultrasonography | Creates images of internal organs using sound waves | Assessing ovarian structure and diagnosing PCOS in FTM individuals3 |
| Hormone Level Assays | Measures concentrations of specific hormones in blood | Evaluating testosterone, estrogen, and other hormone levels3 |
These findings challenge simplistic assumptions that FTM individuals' sexual interests would necessarily mirror those of biological men. The researchers suggested that the characteristics of sexual interest in FTM transsexual persons are not identical to those of biological men, highlighting the complexity of how gender identity relates to sexual arousal patterns8 .
The distinctive features of female-to-male transsexualism in Japan—from the unusual sex ratio to the high prevalence of PCOS and unique surgical preferences—highlight the complex interplay of biological, psychological, and cultural factors that shape gender identity. These findings challenge us to move beyond one-size-fits-all models of transgender healthcare and understanding.
The association with PCOS deserves greater research attention as it may illuminate underlying mechanisms.
Legal and cultural contexts significantly impact how transgender individuals navigate identities and transitions.
Findings remind us of the tremendous diversity within transgender experiences across cultures.
As research in this field continues to evolve, several key insights emerge. First, the biological correlates of gender identity, such as the association with PCOS, deserve greater research attention as they may illuminate underlying mechanisms. Second, cultural and legal contexts significantly impact how transgender individuals navigate their identities and transitions, as seen in Japan's surgical preferences and barriers.
Perhaps most importantly, these findings remind us of the tremendous diversity within transgender experiences across different cultures and individuals. As one Japanese study participant noted, the desire for medical transition stems from multiple factors—some seeking "mental stability," others wanting to reduce gender dysphoria, and others still pursuing their "true self"1 .
While significant progress has been made in understanding gender identity, much remains to be discovered. Future research that continues to explore both the universal and culture-specific aspects of gender identity will further enhance our ability to support the health and well-being of transgender individuals worldwide.