A 19-year-old woman presents with cyclic pelvic pain since menarche, no menstrual flow visible per vagina, and a bluish bulge at the introitus. MRI pelvis shows a distended vagina filled with haematocolpos. The diagnosis and the embryological structure whose failure to perforate caused this condition are:
- A Imperforate hymen; hymen (epithelial plate at the urogenital sinus–Müllerian duct junction) ✓
- B Transverse vaginal septum; lateral plate mesoderm
- C Cervical stenosis; cervical Müllerian epithelium
- D MRKH syndrome; Müllerian duct canalisation failure
Correct answer: A. Imperforate hymen; hymen (epithelial plate at the urogenital sinus–Müllerian duct junction)
Explanation
An imperforate hymen is the most common cause of haematocolpos in adolescents. The hymen represents the epithelial plate at the junction of the Müllerian-derived vaginal plate and the urogenital sinus. Normally this membrane perforates at the 5th month of fetal life; failure results in an imperforate hymen. The diagnosis is confirmed by the bluish bulge (haematocolpos transmitting through the hymen) and haematometra on imaging. Treatment is cruciate incision of the hymen. Transverse vaginal septum occurs higher in the vagina and does not produce a visible bulge.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.