Injury to the muscles of the back passage (anal canal) is a relatively common problem. This injury can result in problems with bowel control later in life and usually occurs during vaginal childbirth (commonly referred to as 3rd and 4th degree perineal tears). Currently women who have sustained injury to the muscles of the back passage undergo an ultrasound scan by inserting a probe 3 to 4 cms into the back passage. This helps to check if the muscle of the back passage has healed i.e is intact or has a defect. The investigators would like to establish whether a 3D ultrasound scan probe placed outside the vagina can identify the defects and hence avoid inserting the probe into the back passage. In addition to getting the above information using 3D ultrasound scan, the investigators would also like to identify injuries to the pelvic floor muscle (levator ani) in these patients. Which can be diagnosed using the 3D ultrasound probe placed outside the vagina (perineum). Women who sustain injury to this muscle are known to develop prolapse later on in life.

Inclusion Criteria:

• Women who sustained an obstetric anal sphincter injury referred to the perineal clinic

Exclusion Criteria:

• None

Women sustained anal sphincter injury during childbirth being followed up ante or postpartum