This chapter provides an overview of transgender identity, focusing on the experience of gender dysphoria—marked distress caused by a mismatch between one’s gender identity and assigned sex at birth. It notes that around 1.4 million people in the U.S. identify as transgender and discusses how gender affirmation therapy, including hormone treatments, surgeries, and psychotherapy, can help improve mental health and overall well-being. Long-term outcomes show improved psychological and social functioning, with no significant difference in mortality compared to cisgender individuals.

Related: Book: The Plasticity of Sex

This chapter in The Plasticity of Sex highlights a shift in understanding core gender identity—from being shaped solely by social and familial factors to a more complex interplay of genetic, hormonal, and neuroanatomic influences. It emphasizes that the sexually dimorphic brain serves as a key anatomical foundation for psychosexual development, shaped by genes and hormones during prenatal and pubertal stages. The authors call for further research to unravel how these biological and psychosocial factors interact to form gender identity.

Related: Book: The Plasticity of Sex

This article challenges the idea that sex and gender are interchangeable, especially in humans. While classical biology often treats them similarly in animals, human gender behavior is far more diverse than the binary categories of male and female. The paper proposes a three-pillar framework for understanding gender: (1) sex-determining genes, (2) cognitive memory systems involving cellular electrical activity, and (3) a largely overlooked factor—sex-specific calcium (Ca²⁺) homeostasis, referred to as the Calcigender concept. It argues that individual differences in Ca²⁺ regulation contribute to personalized gender behaviors, making traditional labels like heterosexual, homosexual, or transgender overly simplistic and potentially misleading.

This report critiques the common practice in political survey research of using biological sex as a stand-in for gender, arguing that it oversimplifies the complexity of gender identity. The authors introduce a more nuanced measure of gender identification and find that while sex can serve as a proxy for gender in many cases, it fails for about a quarter of respondents. Their findings suggest that incorporating more detailed gender measures improves analytical precision and call for further research to refine how gender is measured in political behavior studies.

This groundbreaking book explores gender and sexuality among Native American communities, highlighting the experiences of two-spirit people—individuals whose identities may blend or defy conventional notions of sex and gender. Through diverse voices, including Native and non-Native perspectives, the book offers an intimate and culturally informed understanding of how two-spirit individuals view themselves, how they are perceived within Native societies, and how scholars have interpreted their roles and traditions.

Gender dysphoria is defined as significant psychological distress resulting from a mismatch between a person’s gender identity and their sex assigned at birth. When present, it may involve a strong desire to change physical characteristics or be recognized as a different gender. Treatment often includes social, legal, and gender affirming care tailored to individual needs. Note: The diagnosis refers specifically to the psychological distress of gender incongruence, not the expression of one's gender identity.

This study investigates the link between access to pubertal suppression during adolescence and adult mental health outcomes among transgender individuals. Based on a survey of over 20,000 transgender adults, researchers found that those who received pubertal suppression had significantly lower odds of lifetime suicidal ideation compared to those who wanted but did not receive it. The findings suggest that timely access to this treatment may contribute to improved long-term mental health for transgender adolescents who seek it.

The Plasticity of Sex offers a wide-ranging, evidence-based exploration of human sexuality, focusing on the biological and clinical dimensions of genomic sex, gender identity, and sexual behavior. It addresses growing public and medical interest in topics like gender diversity, genital ambiguity, and sex transition, aiming to provide a scientifically grounded resource for understanding the complexity and variation of human sexual development.

The Healthline article explains that gender is a spectrum, not a binary, and offers definitions for over 60 gender identities and expressions. It distinguishes gender from sex—emphasizing that gender is a personal, social identity while sex refers to biological traits. The piece explores terms like agender, bigender, genderfluid, and cisgender, and highlights how gender expression can vary widely through clothing, behavior, and presentation. It also stresses the importance of inclusive language and understanding, noting that having diverse terms helps people better articulate and affirm their identities.