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. 2020 Jul 2;31(11):2317–2326. doi: 10.1007/s00192-020-04405-2

Table 2.

Clinical outcomes of obstetric anal sphincter injuries at 3 months postnatally (excluding the 3 patients with rectal buttonhole tears)

Number of women (%) Total
(N = 1147)
3a tear
(n = 422)
3b tear
(n = 420)
3c tear
(n = 160)
Ungraded third-degree tear grade (n = 83) Fourth0degree tear (n = 62) p valuea
OR, 95% CI
p valueb
OR, 95% CI
p valuec
OR, 95% CI
dFlatal incontinence (%) 135 (11.8) 32 (7.6) 61 (14.5) 13 (8.1) 13 (15.9) 16 (25.8)

0.01*

OR = 1.8, 1.2–2.7

0.27

< 0.01*

OR = 2.8, 1.6–5.1

dFaecal incontinence (%) 45 (3.9) 7 (1.7) 13 (3.1) 12 (7.5) 8 (9.8) 5 (8.1)

0.02*

OR = 2.7, 1.1–6.2

0.001*

OR = 3.3, 1.6–7.0

0.08
dFaecal urgency (%) 90 (7.9) 21 (5.0) 31 (7.4) 20 (12.5) 13 (15.9%) 5 (8.1)

0.02*

OR = 1.8, 1.1–3.1

0.01*

OR = 2.2, 1.3–3.8

0.92
Mean St. Mark’s incontinence score ± SD 1.9 ± 3.7 1.1 ± 2.6 1.8 ± 3.5 2.5 ± 4.5 4.3 ± 4.9 1.8 ± 3.6 < 0.01 < 0.01* < 0.01*
Urinary incontinence (%) 189 (16.5) 70 (16.6) 68 (16.2) 22 (13.8) 18 (22.0) 11 (17.7) 0.40 0.46 0.96
Mean ICIQ-UI score 1.9 ± 3.8 1.8 ± 3.7 1.5 ± 3.2 1.6 ± 3.7 5.1 ± 6.5 2.0 ± 4.2 0.33 0.84 0.81
Wound infection (%) 31 (2.7) 6 (1.4) 13 (3.1) 3 (1.9) 6 (7.3) 3 (4.8) 0.16 0.76 0.23
Wound dehiscence (%) 38 (3.3) 5 (1.2) 15 (3.6) 4 (2.5) 9 (11.0) 5 (8.1) 0.71 0.64 0.18
Dyspareunia (%) 27 (2.4) 9 (2.1) 7 (1.7) 3 (1.9) 6 (7.3) 2 (3.2) 0.63 0.98 0.65
Perineal pain (%) 77 (6.7) 21 (5.0) 23 (3.5) 13 (8.1) 15 (18.3) 5 (8.1) 0.42 0.15 0.64
Vaginal adhesion/perineal sinus (%) 13 (1.1) 3 (0.7) 6 (1.4) 1 (0.6) 3 (3.7) 0 0.44 0.61 1.0
Granulation tissue (%) 25 (2.2) 5 (1.2) 8 (1.9) 3 (1.9) 7 (8.5) 2 (3.2) 0.38 0.76 0.67
Stitch migration (%) 4 (0.3) 1 (0.2) 0 0 0 3 (4.8) 0.24 0.66

< 0.01*

OR: 55.1, 5.6–538.0

Fistula (%) 7 (0.06) 0 0 1 (0.63) 3 (3.66) 3 (3.66) 0.14 0.07

0.01*

OR: 6.0, 1.2–30.3

Urogenital prolapse (%) 10 (0.9) 3 (0.7) 1 (0.2) 4 (2.5) 2 (2.4) 0 0.80

0.008*

OR = 5.4, 1.3–21.7

1.0
Anal fissure (%) 29 (2.5) 9 (2.1) 13 (3.1) 4 (2.5) 3 (3.7) 0 0.44 0.93 0.4
Mean size of perineal body 2.5 ± 2.0 2.5 ± 0.7 2.5 ± 0.7 2.5 ± 0.5 2.4 ± 0.6 2.0 ± 0.7 1.0 1.0 < 0.01*
Anal manometry results
   Mean resting pressure (mmHg) ± SD 50.3 ± 14.3 53.1 ± 13.5 50.1 ± 13.6 48.0 ± 16.4 47.3 ± 16.1 40.3 ± 10.4 < 0.01* 0.007* < 0.01*
   Maximum squeeze pressure (mmHg) ± SD 94.6 ± 22.0 93.4 ± 27.3 85.1 ± 26.2 83.6 ± 29.4 81.0 ± 21.9 68.1 ± 19.0 < 0.01* 0.04* < 0.01*
   Maximum cough reflex pressure (mmHg) ± SD 73.6 ± 22.5 79.2 ± 20.8 71.6 ± 21.7 72.8 ± 25.8 71.0 ± 25.7 60.1 ± 14.1 < 0.01* 0.41 < 0.01*
   Maximum incremental rise ± SD 36.6 ± 21.0 40.4 ± 22.7 35.0 ± 20.0 35.5 ± 21.0 33.7 ± 14.9 28.3 ± 15.4 < 0.01* 0.28 < 0.01*
   Mean anal length (cm) ± SD 2.4 ± 0.5 2.4 ± 0.5 2.3 ± 0.5 2.3 ± 0.6 2.2 ± 0.5 2.3 ± 0.6 0.004* 0.43 0.14
Endoanal ultrasound results
   Defect in EAS (%) 213 (18.6) 36 (8.6) 88 (21.0) 43 (26.9) 16 (19.3) 30 (48.4)

< 0.01*

OR = 3.1, 2.1–4.6

< 0.01*

OR = 2.2, 1.5–3.3

< 0.01*

OR: 4.9, 2.9–8.4

   Defect in IAS (%) 196(17.0) 23 (5.5) 67 (16.0) 50 (31.3) 14 (16.9) 42 (67.7)

< 0.01*

OR = 4.4, 2.7–7.0

< 0.01*

OR = 3.9, 2.6–5.9

< 0.01*

OR: 14.5, 8.0–26.1

95% CI = 95% confidence interval; EAS = external anal sphincter; IAS = internal anal sphincter; ICIQ-UI = International Consultation on Incontinence modular Questionnaire for Urinary Incontinence; OR = odds ratio; SD = standard deviation

*Statistically significant p value

a: comparing between 3a and 3b/c tear grade

b: comparing between 3a/b and 3c tear grade

c: comparing between overall third- and fourth-degree tear