A 24-year-old woman presents with primary amenorrhoea. Examination reveals blind vaginal pouch, absent uterus, normally developed secondary sexual characteristics, and scant axillary/pubic hair. Karyotype is 46,XY. The MOST likely diagnosis is:

• A Turner syndrome
• B Complete androgen insensitivity syndrome (CAIS) ✓
• C Mayer-Rokitansky-Küster-Hauser syndrome
• D Congenital adrenal hyperplasia

Explanation

CAIS presents with 46,XY karyotype, absent uterus and fallopian tubes (because testes produce AMH), normal breast development (from peripheral oestradiol conversion), scanty pubic/axillary hair (androgen receptor absent so no androgen-dependent hair), and a blind-ending vagina. MRKH syndrome has 46,XX karyotype with normal ovaries. Turner syndrome has 45,X with infantile secondary sex characteristics. Gonadectomy in CAIS is recommended after pubertal completion due to gonadoblastoma risk.

Reference: Shaw's Textbook of Gynaecology, 17th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.