Definition: is an accumulation of menstrual blood in the vagina caused by stenosis of the vaginal walls or imperforate hymen

Symptoms: pain, particularly just after menstration, with little or no flow of menstrual blood. On examination the vaginal entrance will be found occluded by the hymen, and under the public arch there is an elastic tumor, which, as the accumulation increases, will sxtend above the pubic bone. Rectal examination proves the presence of an elastic, globutar tumor, completely or partially filling the pelvis. A catheter in the bladder will aid in diagnosis.
Investigations
• Abdominal ultrasound.

• MRI scan may be required if the ultrasound result is unclear.

Treatment: evacuation of the fluid under the strictest antiseptic precautions. The tendency to contraction should be guarded against by having the patient wear a glass plug.

Dangers: rupture of a dilated and adherent oviduct. Sepsis, due to infection of contents of vagina. Injury to bladder or rectum
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