Spontaneous rupture or avulsion of the vagina from the cervix during labour is a rare condition. The term colporrhexis describes this obstetric injury and it is subdivided into primary or secondary, spontaneous or traumatic, complete or incomplete. Incomplete colporrhexis includes rupture of the vaginal epithelium and the muscularis, whereas complete involves the overlying peritoneum as well. Primary colporrhexis is a vaginal vault tear not associated with cervical or uterine extension. Secondary colporrhexis cannot be differentiated from a rupture that has originated in the uterus and then extended to involve the vagina (1).
The condition has been associated with high parity, but it has been reported in primigravidae (2). Most cases of primary colporrhexis are of traumatic origin associated with unskilled instrumental delivery. The aetiology of the rarer primary spontaneous colporrhexis is unknown and previous vaginal trauma has been implicated. Precipitate labour and use of oxytocics in labour are other factors described (1,3). A misdirection of the uterine axis due to a pendulous abdomen leading to marked anteversion of the uterus, ventrofixation of the uterus, evacuation of a full rectum after an enema, and prolapse leading to altered blood supply to the vagina are the other factors responsible. I describe here a case of primary spontaneous complete colporrhexis.