Outcomes
Primary and secondary outcomes are reported in Table 3. At W6-8 after
delivery, anal incontinence was not statistically different between
trial arms, nor was post-partum transient anal incontinence (11.7% in
the CS arm vs 25.0% in the VD arm (absolute risk difference [95%
CI]: -13.3 [-25.1 to 0.0]).
At M6, the median [IQR] Vaizey score for anal incontinence was 1/24
[0-4] in the CS arm vs 1/24 [0-3] in the VD arm (p=0.34) (figure
2). This primary outcome was actually measured at a median [IQR]
time of 8.0 [6.8 – 11.2] months post-partum. When comparing Vaizey
scores at inclusion and at the M6 visit, the results did not differ
between the CS and VD groups (median (IQR) differences 0.0
[-1.5-2.0] and 0.0 [0.0-1.0], respectively, p = 0.9825). The
effect of trial arm on Vaizey score at M6 differed between women with
Vaizey score at inclusion <5 and women with Vaizey score at
inclusion ≥5 (significant interaction, p=0.008). Post-hoc subgroup
analyses showed that in the subgroup of 27 women with a Vaizey score
before delivery ≥5, Vaizey score at M6 were significantly lower in the
CS than in the VD arm (median 3 IQR [0-7] vs 6 [3.5-8.5],
p=0.026).
At M6, there was no statistically significant difference between groups
for urinary incontinence (MUH score), sexual function (FSFI) and
physical and mental quality of life assessed with SF12.
Regarding maternal morbidity, 4 (4.9%) patients had at least one minor
complication in the VD arm and 8 (8.8%) in the CS arm, including 3
(3.3%) anesthetic complications (headaches) in the CS arm and none in
the VD arm. For neonatal outcomes, 5 (6.1%) had at least one
complication in the VD arm including 4 transfers to neonatal care units
(2 for respiratory distress and 2 for infection) versus none in the CS
arm.
Among the 222 randomized women, 125 (56.3%) had post-partum
endosonography at the M6 visit, 61 (54.5%) in the VD arm and 64
(58.2%) in the CS arm. Baseline characteristics of these women did not
differ from those without endosonography (see supplementary appendix).
External sphincter lesions deteriorated more frequently in the VD arm
than in the CS arm (11 (22.4%) women vs 1 (2.2%), absolute risk
difference -20.2 [95% CI: -31.7 to -7.6]), but no additional
internal sphincter lesions were observed.