Secondary sex characteristics are changes that typically occur at the time of puberty. They can include body hair growth, change in pitch of voice, genital growth, breast development, muscle development and growth of the Adam’s apple.

When a child is born with a DSD and his or her sex is unclear, the child is given a "sex assignment,” which means the parents decide whether to raise the child as a boy or a girl. Sex assignment is a system of labeling a child and treating a child as a boy or a girl. (For this reason, no surgery is required for sex assignment.)

This is the term for the step-by-step changes that relate to the biological (physical) features of a person’s sex. The development of sex begins at conception with the combining of sex chromosomes from the mother’s egg and the father’s sperm. Sex development continues in the womb with the prenatal development of the internal sex organs (including the gonads) and the external sex organs (like the penis, clitoris, labia, and scrotum). For most people, sex development continues naturally little by little through all stages of life, including most noticeably at puberty (which brings many changes including altered sexual arousability, fat distribution, voice pitch, hairline, pubic, underarm, and body hair, genital and nipple appearance, breast development, skin oil and texture, and body odor) and at menopause.

Sex differentiation is the process by which males and females grow to be different from each other. Until about seven weeks after conception, all embryos regardless of their chromosomal makeup have the same structures of the gonads and genitalia (genital folds, genital ridges, genital tubercles, Mullerian ducts, and Wolffian ducts). Most develop according to what is considered standard for males or females, but some develop differently.

Sex hormones interact with cells that have functioning androgen or estrogen receptors, and play important roles in inducing the body changes affecting sex anatomy both before and after birth. Sex hormones are produced by the gonads, and also by the adrenal glands.

Sexual orientation refers to whether an individual is sexually attracted to men or women, both, or neither. If a person is identified as a man and is attracted to a man, he is said to be homosexual. If a person is identified as a woman and is attracted to men, she is said to be heterosexual. Most people in fact have complex sexual orientations; that is, their sense of sexual attraction goes beyond just other people’s gender identities. People do not choose their sexual orientations, though they do choose whether to act on their sexual desires.

A social worker is a mental health professional who can offer support and counseling. The social worker knows much about children’s psychological and emotional development, and how to help families when there is a medical or social issue in a family. Social workers in the clinical setting help to connect families to resources inside and outside the medical facility. They often know much about how to deal with bullying, how to navigate school systems, etc.

Swyer syndrome is a synonym for XY gonadal dysgenesis. Synonyms: XY gonadal dysgenesis