Complete androgen insensitivity — structured oral station (12 minutes)

Opening prompt — "Explain the diagnosis from receptor to phenotype."

Model response — the mechanism: ^[1]

• "This is complete androgen insensitivity syndrome. She is 46,XY with normally differentiated testes making male-range testosterone and anti-Mullerian hormone. The androgen receptor is defective, so androgen cannot act on any target tissue."
• "Follow the two signals separately: testosterone cannot virilise her, so her external genitalia are female; AMH acts normally, so the Mullerian system regressed in fetal life — hence no uterus and a short blind vagina. At puberty, peripheral aromatisation converts testosterone to oestradiol, giving normal breast development, while androgen-dependent pubic and axillary hair stay scanty. That last point is the giveaway on examination."^[1]

Probe 1 — "The registrar next door says this could be Mullerian agenesis. Settle it."

• "Three questions separate them. First, the androgen-dependent hair: MRKH has normal pubic hair; CAIS is scanty. Second, the karyotype and gonadotrophins: MRKH is 46,XX with normal FSH and LH; CAIS is 46,XY with a raised LH. Third, the gonads: MRKH has functional ovaries and can parent genetically through surrogacy; CAIS has testes that carry a germ-cell tumour risk. This patient's scanty hair, 46,XY, elevated LH and male-range testosterone make CAIS, not MRKH."^[1][5]

Probe 2 — "She asked whether 'these lumps in my groin' need to come out. Defend your gonad-management plan."

• "The plan turns on age. Before and through puberty I retain the testes: the germ-cell tumour risk is very low — of the order of 1 to 2 per cent — and retaining them lets spontaneous oestrogen-driven puberty happen with lifelong bone and cardiovascular benefit. After puberty the risk profile changes: Deans and colleagues pooled the literature in 2012 and estimated the adult risk at about 14 per cent, with reports ranging to 22 per cent."
• "So I offer laparoscopic bilateral gonadectomy shortly after puberty completes, with counselling that surveillance — imaging and tumour markers — cannot reliably exclude an early tumour if she chooses to keep her gonads. Deans' series also showed that adult women increasingly defer or decline, citing surgical risk and a reluctance to take lifelong hormone replacement; I respect an informed choice either way and document it. If the gonads come out I start oestrogen replacement and protect bone with calcium, vitamin D and bone-density surveillance."^[1][2]

Probe 3 — "What do you tell her about sex and children?"

Communication domain — demonstrate empathy out loud while answering: ^[3][4]

• "Sexual function: her short vagina does not preclude satisfying sexual function, and if she wants more length, graduated vaginal dilation — taught by an experienced team, at her pace — succeeds in the large majority. I would not offer surgery as a default."
• "Fertility: she cannot carry a pregnancy and has no oocytes, so her parenting routes are adoption or a partner's or donor gametes with surrogacy where she has a genetic link through family — and I say this plainly, because dishonesty here echoes for life."
• "Identity: CAIS women identify and live as women. The condition is about receptor biology, not about who she is."^[4]

Probe 4 — "Walk me through the disclosure conversation. What do you say, and what must you not say?"

This is a scored communication station — slow down, sit at her level, use her name: ^[3][4]

• "I tell her the truth, staged and in plain words: your body makes hormones at puberty normally but responds to them in a particular way; you were born with a variation in how your sex chromosomes and tissues talk to each other; many women have this and most live full female lives; you will not have periods and you will not carry a pregnancy, and we can talk about every route to children when you want to."
• "I use the word 'difference' or 'variation' rather than 'disorder', I never use older terms, and I do not disclose a karyotype as a verdict about her sex. I offer written information, a named psychologist, and a peer-support group, and I tell her the full answer now — the days of managing CAIS by concealing the 46,XY result are over."^[4]

Probe 5 — "Her mother asks: 'Did I cause this, and can it happen again?'"

• "I reassure on causation: nothing she did or took in pregnancy causes a new androgen-receptor mutation. On recurrence: because the receptor gene sits on the X chromosome, her mother and sisters warrant carrier testing; a carrier has a fifty per cent chance of passing the variant to each 46,XY child. Genetic counselling is part of the management, not an afterthought."^[1][4]