Odds ratio (OR) and 95% confidence interval (CI) for dysmenorrhoea in association with self perceived stress in the preceding menstrual cycle and a reported history of dysmenorrhoea at baseline
| History of dysmenorrhoea‡ | Stress in the preceding cycles | Total cycles (% dysmenorrhoea) | OR†§ | 95% CI§ |
|---|---|---|---|---|
| ***p<0.001. | ||||
| †The outcome was defined as a binary variable adjusted for age, BMI, shift work, dust exposure, cycle length, education, and passive smoking. | ||||
| ‡History of dysmenorrhoea refers to experience of dysmenorrhoea within a year prior to enrolment, obtained from baseline questionnaire. | ||||
| §OR, odds ratio; CI, confidence interval. | ||||
| ¶Reference group. | ||||
| No | Low | 257 (10.9) | 1.0¶ | – |
| No | Medium | 243 (17.3) | 1.3 | 0.7 to 2.2 |
| No | High | 73 (24.7) | 2.1 | 0.9 to 5.2 |
| Yes | Low | 237 (33.8) | 4.2 | 2.3 to 7.6*** |
| Yes | Medium | 252 (39.7) | 4.6 | 2.6 to 8.3*** |
| Yes | High | 98 (58.2) | 10.4 | 4.9 to 22.3*** |