Elevated oxytocin levels and oxytocin receptor gene expression in female-to-male transgender individuals.
Dastorani. Majid M; Shahini. Najmeh N; Livani. Amirreza A; Saghaeian Jazi. Marie M; Asadi. Jahanbakhsh J
Key Findings
- Plasma oxytocin was significantly higher in female‑to‑male (FtM) transgender participants than in cisgender female controls.
- Oxytocin receptor (OXTR) gene expression was significantly higher in FtM participants who self‑administered testosterone compared to controls.
- The study suggests a possible neurobiological link between oxytocin signaling and gender dysphoria, but causality remains unclear.
Practical Outcomes
- For most biohackers, the findings have limited immediate use. The data do not provide dosage guidance, safety information, or performance benefits for oxytocin supplementation. Until further research clarifies whether oxytocin modulation affects mood, cognition, or metabolic health in broader populations, this study remains primarily of academic interest.
Summary
The study found that people assigned female at birth who transition to male have higher blood levels of oxytocin and, when they also self‑inject testosterone, higher expression of the oxytocin receptor gene compared to cisgender women. This is the first report linking oxytocin biology to gender dysphoria, but it doesn’t tell us how to use oxytocin for health or performance.
Abstract
Gender dysphoria (GD) is defined as a condition wherein a person's gender identity does not align with the sex assigned at birth. Oxytocin (OXT) is an essential neuromodulator involved in cognition and socio-emotional processing. Its central effects are exerted via oxytocin receptors (OXTR). Recent studies indicated that the changes in the levels of OXTR may influence the course of some mental disorders (obsessive-compulsive disorders, schizophrenia, depression and autism). Understanding the neurobiological underpinnings of GD, particularly the involvement of OXT and OXTR, could provide beneficial insights into the mechanisms underlying this condition. In the present study, 18 Female-to-Male (FtM) transgenders, 11 FtM transgenders with self-injection of testosterone (FtM-T), and 30 control cis-females were included. Plasma levels of hormones of OXT, estradiol, progesterone, LH, FSH, free testosterone, and testosterone were evaluated with an enzyme-linked immunosorbent assay (ELISA) kit. The whole blood mRNA expression of OXTR was determined via RT-qPCR. Our results showed a statistically significant increase in OXT plasma level in FtM group compared to control group (P = 0.032). Also, OXTR gene expression was significantly high in FtM-T group compared to cis-females group (P = 0.004). This is the first demonstration of increased plasma OXT levels in FtM transgenders and OXTR gene expression in FtM-T transgenders compared to the cis-females group. The results of this study can create a new approach to understanding the underlying mechanism of gender dysphoria. Further studies are necessary to ascertain whether this contributes to or is a consequence of GD symptomatology.
Study Information
pubmed
2025
2025-11-28T00:00:00.000Z
10.1038/s41598-025-26845-w
51