[citation needed] XY individuals affected by CAIS develop a normal external female habitus, despite the presence of a Y chromosome,[1][5][6][7][8][9] but internally, they will lack a uterus, and the vaginal cavity will be shallow, while the gonads, which differentiated into testes in the earlier separate process also triggered by their Y chromosome, will remain undescended in the place.

[15] Individuals with complete androgen insensitivity syndrome (grades 6 and 7 on the Quigley scale) are born with an external female phenotype, without any signs of genital masculinization, despite having a 46,XY karyotype.

[26][27] They may be located intra-abdominally, at the internal inguinal ring, or may herniate into the labia majora, often leading to the discovery of the condition.

[20] Immature sperm cells in the testes do not mature past an early stage, as sensitivity to androgens is required in order for spermatogenesis to complete.

[34] Wolffian structures (the epididymides, vasa deferentia, and seminal vesicles) are typically absent, but will develop at least partially in approximately 30% of cases, depending on which mutation is causing the CAIS.

[35] The prostate, like the external male genitalia, cannot masculinize in the absence of androgen receptor function, and thus remains in the female form.

[18][36][37][38] The Müllerian system typically regresses the same way it does in unaffected male fetuses due to anti-Müllerian hormone originating from the Sertoli cells of the testes.

[38] Other subtle differences that have been reported include slightly longer limbs and larger hands and feet due to a proportionally greater stature than unaffected women,[40][41][42] larger teeth,[43][44] minimal or no acne,[45] well developed breasts,[46] a greater incidence of meibomian gland dysfunction (i.e. dry eye syndromes and light sensitivity),[47] and dry skin and hair resulting from a lack of sebum production.

[52][53][54] The production rates of testosterone, estradiol, and estrone have been reported to be higher in gonadally intact with CAIS than in men.

[60][61][62][63][64][65] Some have hypothesized that the decreased bone mineral density observed in women with CAIS is related to the timing of gonadectomy and inadequate estrogen supplementation.

[60][61][62][63] CAIS is also associated with an increased risk for gonadal tumors (e.g. germ cell malignancy) in adulthood if gonadectomy is not performed.

[1][19] A diagnosis of CAIS or Swyer syndrome can be made in utero by comparing a karyotype obtained by amniocentesis with the external genitalia of the fetus during a prenatal ultrasound.

[18] If the affected individual is a child or infant, it is generally up to the parents, often in conjunction with a psychologist, to decide when to disclose the diagnosis.

Areas of management include sex assignment, genitoplasty, gonadectomy in relation to tumor risk, hormone replacement therapy, and genetic and psychological counseling.

[1] They are born with an external phenotype of a typical female and are thought to be usually heterosexual with a female gender identity;[41][82] however, some research has suggested that individuals with CAIS are more likely to have more variable gender outcomes and a non-primarily heterosexual sexual orientation than relatively similar control groups of those with MRKH syndrome and PCOS, contradicting this belief.

Research suggests that testosterone is at least as beneficial as estrogen replacement therapy and possibly improves outcomes in certain areas of well-being.

If this is the case, annual imaging of the gonads via MRI or ultrasound is recommended in order to monitor for signs of malignancy.

[1] Androgen replacement has been reported to increase a sense of well-being in gonadectomized people with CAIS, although the mechanism by which this benefit is achieved is not well understood.

[18] Parents of children with CAIS need considerable support in planning and implementing disclosure for their child once the diagnosis has been established.

[1][18] For parents with young children, information disclosure is an ongoing, collaborative process requiring an individualized approach that evolves in concordance with the child's cognitive and psychological development.

[25] Surgical intervention should only be considered after non-surgical pressure dilation methods have failed to produce a satisfactory result.

[96] Ileal or cecal segments may be problematic because of a shorter mesentery, which may produce tension on the neovagina, leading to stenosis.

[96] The sigmoid neovagina is thought to be self-lubricating, without the excess mucus production associated with segments of small bowel.

Long-term studies indicate that with appropriate medical and psychological treatment, those with CAIS can be satisfied with their sexual function and psychosexual development.

[104][105] The condition became more widely known after it was reviewed and named testicular feminization by American gynecologist John McLean Morris in 1953.