Table 4.
Changes in vaginal resting pressure (VRP), pelvic floor muscle (PFM) strength and PFM endurance between delivery modes from 6 to 12 months postpartum and from mid-pregnancy to 12 months postpartum (N=235)
| Variable | NVD (n=157) vs. CS (n= 35) | IVD (n=43) vs. CS (n= 35) | NVD (n=157) vs. IVD (n=43) | ||||
|---|---|---|---|---|---|---|---|
| Mean difference (95% CI) | P value | Mean difference (95% CI) | P value | Mean difference (95% CI) | P value | ||
| VRP | ∆ 6 months pp – 12 months pp (cmH2O) | 0.3 (−1.4, 2.0) | 0.739 | −0.01 (−2.1, 2.1) | 0.991 | −0.3 (−1.8, 1.2) | 0.694 |
| ∆ gestational week 18–22–12 months pp (cmH2O) | 4.3 (1.5, 7.1) | 0.003 | 5.7 (2.5, 9.0) | <0.001 | 1.5 (−1.1, 4.0) | 0.256 | |
| PFM strength | ∆ 6 months pp–12 mo. pp. (cmH2O) | −0.4 (−3.1, 2.3) | 0.779 | 0.2 (−3.5, 3.9) | 0.930 | 0.5 (−1.8, 2.9) | 0.647 |
| ∆ gestational week 18–22–12 months pp (cmH2O) | 7.3 (2.8, 11.8) | <0.001 | 10.1 (4.4, 15.8) | <0.001 | 2.8 (−1.5, 7.0) | 0.199 | |
| PFM endurance | ∆ 6 months pp –12 months pp (cmH2Osec) | 7.8 (−16.9, 32.4) | 0.536 | 10.2 (−20.8, 41.1) | 0.515 | 2.4 (−19.1, 23.9) | 0.826 |
| ∆ gestational week 18–22–12 months pp (cmH2Osec) | 43.6 (−1.4, 88.5) | 0.057 | 68.7 (21.8, 115.5) | 0.005 | 25.1 (−16.5, 66.7) | 0.193 | |
Values are presented with mean difference and 95% CIs
PFM strength is calculated as the mean of three maximal voluntary contractions. PFM endurance is reported during a 10-s sustained maximal contraction
Positive values for mean difference indicate greater change in the PFM variable for the former delivery mode in the comparison
Negative values for mean difference indicate minor change in the PFM variable for the former delivery mode in the comparison
CI confidence interval, CS cesarean section, IVD instrumental vaginal delivery, NVD normal vaginal delivery, PFM pelvic floor muscle VRP vaginal resting pressure, ∆ change
Independent-samples t test