Examples from literature

• If there seems to be a persistent disposition of the circular fibers of the cervix to contract, and thus close the canal, a surgical operation will be necessary to insure permanent relief. 
• In many cases, the contracted and narrowed condition of the canal of the cervix seems to be a congenital deformity, for we can trace it to no perceptible cause. 
• Perforation of the vaginal walls, bladder, cervix, or uterus, may follow their use.