- It is also known as hematocalpos,is a condition where menstruation occurs but is not visible due to obstruction of the outflow track.
- Specifically the endometrium is shed,but a congenital obstruction such as vaginal septum or onpart of the hymen retains the menstrual flow.
.mullerian duct aromalies.
.blunt pelivc trauma.
.acquired vaginal atresia,cervical stensis