Participants
Women having a history of a traumatic first delivery were first assessed
for eligibility for anal ultrasonographic examination by the
obstetrician at clinic visits in the third trimester of their second
pregnancy. Women were eligible if they had a first vaginal instrumental
delivery with forceps (vacuum extractions were not considered) and/or
with a diagnosis of a third-degree perineal tear, had no self-reported
anal incontinence at inclusion, were 18 years old or over, and signed
informed consent to participate. The main exclusion criteria were a
history of anal surgery, a fourth-degree perineal tear at the first
delivery, self-reported AI, defined as involuntary leakage of gas or
stools and any other indication for planned CS for non-proctologic
reasons.
After inclusion, women had a proctological evaluation including the
Vaizey score 18 and anal endosonography with the same
expert operator (LA).The Vaizey score was chosen for its sensitivity by
accounting for 24 components of AI, including the loss of flatus with or
without the loss of liquid and solid stool, pad use, stool urgency,
medication use and quality of life. Endosonography was performed with an
ultrasound scanner with a rotating rectal probe, a multifrequency of
7-10 MHz,and a hard sonolucent plastic cone (Bruel and Kjaer,Naemm,
Denmark). Three anal canal levels (upper,middle, and lower) were studied
and recorded (videorecorder, Sony, Tokyo, Japan). External anal
sphincter lesions, as well as any internal sphincter lesions, were
characterized as defined by Law et al. 19, according
to defect angle and defined as severe if more than 90°. In case of anal
sphincter lesions at endosonography, the patient was eligible for the
randomized part of the trial.