TABLE 1.
Peripartum hysterectomy rates and incidence rate ratios according to associated factors
| Hysterectomy n (%) | Deliveries a n (%) | Hysterectomy rate per 1000 deliveries (95% CI) | Crude IRR (95% CI) | Adjusted IRR (95% CI) b | |
|---|---|---|---|---|---|
| All | 42 | 96 313 | 0.44 (0.31–0.59) | ||
| Age at delivery, years | 96 312 | ||||
| <30 | 2 (4.8) | 29 315 (30.4) | 0.07 (0.01–0.25) | 1.00 (ref) | 1.00 (ref) |
| 30–39 | 26 (61.9) | 61 762 (64.1) | 0.42 (0.27–0.62) | 6.16 (1.46–26.0) | 3.66 (0.80–16.6) |
| ≥40 | 14 (33.3) | 5235 (5.5) | 2.67 (1.46–4.49) | 39.2 (8.91–172.2) | 12.3 (2.67–56.7) |
| Gestational age, weeks | 95 907 | ||||
| ≥37 | 26 (61.9) | 89 365 (93.2) | 0.29 (0.19–0.43) | 1.00 (ref) | |
| <37 | 16 (38.1) | 6542 (6.8) | 2.45 (1.4–3.97) | 8.41 (4.51–15.7) | |
|
Parity |
96 313 | ||||
| Para 0 | 9 (21.4) | 47 682 (49.5) | 0.19 (0.09–0.36) | 1.00 (ref) | 1.00 (ref) |
| Para 1 | 14 (33.3) | 33 549 (34.8) | 0.45 (0.25–0.74) | 2.21 (0.96–5.11) | 0.91 (0.35–2.37) |
| Para ≥2 | 19 (45.3) | 15 082 (15.7) | 1.26 (0.76–1.97) | 6.67 (3.02–14.8) | 2.24 (0.88–5.69) |
|
Country of origin |
96 313 | ||||
| Norway | 17 (40.5) | 64 033 (66.5) | 0.27 (0.15–0.43) | 1.00 (ref) | |
| High income countries | 3 (7.1) | 8491 (8.8) | 0.35 (0.07–1.03) | 1.33 (0.39–4.54) | |
| LMIC | 21 (50.0) | 22 580 (23.5) | 0.93 (0.58–1.42) | 3.50 (1.85–6.64) | |
| Unknown | 1 (2.4) | 1209 (1.2) | 0.83 (0.02–4.61) | 3.12 (0.41–23.41) | |
|
Multiple pregnancy |
|||||
| No | 39 (92.9) | 94 162 (97.8) | 0.41 (0.29–0.57) | 1.00 (ref) | 1.00 (ref) |
| Yes | 3 (7.1) | 2151 (2.2) | 1.39 (0.29–4.08) | 3.37 (1.04–10.9) | 3.68 (1.12–12.1) |
|
Previous CS |
96 313 | ||||
| No | 20 (47.6) | 86 779 (90.1) | 0.23 (0.14–0.36) | 1.00 (ref) | 1.00 (ref) |
| Yes | 22 (52.4) | 9534 (9.9) | 2.31 (1.45–3.49) | 9.10 (4.97–16.7) | 4.69 (2.27–9.66) |
|
Mode of delivery |
96 313 | ||||
| Vaginal delivery | 8 (19.0) | 77 038 (80.0) | 0.1 (0.04–0.2) | 1.00 (ref) | |
| CS | 34 (81.0) | 19 275 (20.0) | 1.76 (1.22–2.46) | 17.0 (7.87–36.7) | |
|
Placenta previa |
96 313 | ||||
| No | 28 (66.7) | 95 942 (99.6) | 0.29 (0.19–0.42) | 1.00 (ref) | 1.00 (ref) |
| Yes | 14 (33.3) | 371 (0.4) | 37.7 (20.6–63.3) | 129.3 (68.1–245.6) | 71.6 (36.7–139.7) |
Statistically significant results (P < 0.05) are presented in bold.
CI, confidence interval; IRR, incidence rate ratio; LMIC, low‐ and middle‐income countries; CS, cesarean section.
a
Number of deliveries at Oslo University Hospital provided by+ the Medical Birth Registry of Norway.
b
Adjusted for age at delivery, parity, previous cesarean section, multiple pregnancy and placenta previa.