XX gonadal dysgenesis is a type of female hypogonadism in which no functional ovaries are present to induce puberty in an otherwise normal girl whose karyotype is found to be 46,XX. With nonfunctional streak ovaries, she is low in estrogen levels (hypoestrogenic) and has high levels of FSH and LH. Estrogen and progesterone therapy is usually then commenced. Some cases are considered a severe version of premature ovarian failure where the ovaries fail before puberty.

Some forms of XX gonadal dysgenesis occurs with sensorineural deafness. This type is also known as Perrault syndrome, an autosomal recessive disease affecting both sexes. Males present only with the deafness.

The term "pure gonadal dysgenesis" (PGD) has been used to distinguish a group of patients from gonadal dysgenesis related to Turner syndrome. In the latter a distinct chromosomal aberration is present, while in PGD the chromosomal constellation is either 46,XX or 46,XY. Thus XX gonadal dysgenesis is also referred to as PGD, 46 XX, and XY gonadal dysgenesis as PGD, 46,XY or Swyer syndrome. Patients with PGD have a normal chromosomal constellation but may have localized genetic alterations.