Disorders of sex development (DSDs) are conditions in which the reproductive organs and genitals do not develop normally. People with DSDs have a mix of male and female sexual characteristics.
There are different types of DSDs:
- A person may be genetically female (they have two X sex chromosomes), but have genitals that appear more masculine. They may, for example, have an enlarged clitoris that resembles a penis and their labia (lips surrounding the vagina) may be fused together. The most common cause for this type of DSD is a metabolic condition called congenital adrenal hyperplasia (CAH), which also affects other aspects of health.
- Another type of DSD occurs when a person is genetically male (having one X and one Y sex chromosome), but the genitals appear more female. This type of DSD is most often caused by complete or partial androgen insensitivity syndrome (AIS), which causes the body to respond abnormally to male hormones.
- People with male, female, or mixed chromosomes can be born with both ovarian and testicular tissue. In this type of DSD, the genitals can appear female, male or a mix of both.
- Sometimes sexual organs are normally formed as either male or female, but growth and sexual development are disrupted at puberty. Individuals with this type of DSD have an abnormal chromosome arrangement, such as a missing or extra X chromosome. Females with a DSD called Turner syndrome, for example, are missing an X chromosome and are usually infertile and of shorter than average height.
When a DSD is suspected, tests are used to confirm the diagnosis. These include chromosome analyses, blood tests to measure hormone levels, and imaging studies to examine internal sex organs.
