Table IV.
Crude and adjusted ORs with 95% CIs for the impact of lifetime duration of oral contraceptives on pelvic girdle pain in 91 721 Norwegian pregnancies (1999–2008).
| Variables | No. persons | Pelvic girdle pain |
||
|---|---|---|---|---|
| No. cases (%) | Crude OR (95% CI) | Adjusted ORa (95% CI) | ||
| Combined oral contraceptive pills | ||||
| Never user | 22 437 | 3657 (16.3) | Ref. | Ref. |
| <1 year | 6043 | 1010 (16.7) | 1.03 (0.95–1.11) | 1.03 (0.95–1.12) |
| 1–3 years | 15 758 | 2436 (15.5) | 0.94 (0.89–0.99)* | 0.99 (0.93–1.05) |
| 4–6 years | 18 333 | 2658 (14.5) | 0.87 (0.82–0.92)** | 1.00 (0.94–1.06) |
| 7–9 years | 15 981 | 2067 (12.9) | 0.76 (0.72–0.81)** | 0.94 (0.88–1.00)* |
| ≥10 years | 13 169 | 1786 (13.6) | 0.81 (0.76–0.86)** | 1.04 (0.97–1.11) |
| Progestin-only contraceptive pills | ||||
| Never user | 80 788 | 11 713 (14.5) | Ref. | Ref. |
| <1 year | 6448 | 1184 (18,4) | 1.33 (1.24–1.42)** | 1.05 (0.97–1.12) |
| 1–3 years | 3469 | 552 (15.9) | 1.12 (1.02–1.23)* | 0.97 (0.88–1.07) |
| 4–6 years | 564 | 86 (15.2) | 1.06 (0.84–1.34) | 1.06 (0.84–1.35) |
| 7–9 years | 256 | 43 (16.8) | 1.19 (0.86–1.65) | 1.14 (0.81–1.62) |
| ≥10 years | 196 | 36 (18.4) | 1.33 (0.92–1.92) | 1.49 (1.01–2.20)* |
CI, confidence interval; OR, odds ratio.
aAdjusted for maternal age, parity, educational level, BMI, age at menarche, other pain conditions and premenstrual depressive symptoms (n= 86 139).
*Statistically significant at 0.05 level.
**Statistically significant at 0.001 level.