Disorders of sex development  Disorders of sex development (DSDs), also known as differences in sex development, diverse sex development and variations in sex characteristics (VSC), are medical conditions involving the reproductive system. More specifically, these terms refer to "congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical." The term has been controversial, and research has shown that affected people experience a negative impact, with the terminology impacting choice and utilization of health care providers. The World Health Organization and many medical journals still reference DSDs as intersex traits or conditions. The Council of Europe and Inter-American Commission on Human Rights have called for a review of medical classifications that unnecessarily medicalize intersex traits. DSDs are medical conditions involving the way the reproductive system develops from infancy (and before birth) through young adulthood. There are several types of DSDs and their effect on the external and internal reproductive organs varies greatly. A frequently-used social and medical adjective for people with DSDs is "intersex". Parents with DSD children and clinicians involved in DSD treatment usually try to make clear distinctions between biological sex, social gender, and sexual orientation. This helps reduce confusion about the differences between being intersex, being transgender, and being gay/lesbian. The most common DSD is congenital adrenal hyperplasia (CAH), which results in a person with female (XX) chromosomes having genitals that look somewhat masculine. In mild cases, CAH results in a slightly enlarged clitoris, while in more severe cases it can be difficult to decide on observation whether a baby is male or female (ambiguous genitalia). CAH is caused by a problem with the adrenal glands and is usually treated by taking a daily medication to replace or supplement the missing adrenal hormones. (When this adrenal problem occurs in people with male (XY) chromosomes, the result is over-masculinization and premature puberty). Another common DSD is androgen insensitivity syndrome (AIS), also known as "testicular feminising syndrome" in which a person with male (XY) chromosomes does not respond to testosterone in the usual way. This results in a body that to some degree has a feminine appearance. In complete androgen insensitivity syndrome (CAIS) the result is a totally feminine appearance, including typical female breast development. Consequently, most young women with CAIS are unaware of their condition until the early teen years when they fail to menstruate. In the milder form, called partial androgen insensitivity syndrome (PAIS), the genitals can vary from mostly female to almost completely male.