Your caregiver may order some tests to assess how your 3rd or 4th degree tear has healed, especially if you are experiencing ongoing problems such as being incontinent of wind or bowel motions. These tests do not tend to be performed soon after the birth, rather the weeks and months that follow the repair of the tear.
The tests can include:
Ultrasound. An ultrasound of the lower rectum involves an ultrasound probe being placed inside the anus (called anal endosonography). This examines the degree of healing of the tear or the extent of any existing injury of the internal and external anal sphincter.
Measuring rectal pressure. This test is called ano-rectal manometry. A probe is placed into the rectum, measuring the pressure differences between when the woman's pelvic floor is resting and when it is 'straining' (or the action of opening the bowels). This can indicate to the caregiver how efficiently the anal sphincter is functioning.