Crude rate and crude and adjusted HRs of PID for all women and classified by exposure to chlamydia and gonorrhoea
| Number of PID cases | Crude rate of PID, per 100 women per year (95% CI) | Crude HR (95% CI) | p | Adjusted* HR (95% CI) (*incident case of gonorrhoea, history of chlamydia and gonorrhoea at enrolment) | p | |
| All women | 38 | 11.33 (8.22 to 15.56) | ||||
| Incident case of chlamydia | ||||||
| No | 26 | 10.10 (6.88 to 14.83) | reference | reference | ||
| Yes | 12 | 17.20 (9.77 to 30.28) | 1.87 (0.92 to 3.79) | 0.083 | 1.49 (0.65 to 3.40) | 0.341 |
| Incident case of gonorrhoea | ||||||
| No | 32 | 11.07 (7.83 to 15.66) | reference | reference | ||
| Yes | 6 | 12.90 (5.80 to 28.72) | 1.36 (0.55 to 3.38) | 0.503 | 0.82 (0.28 to 2.39) | 0.715 |
| Past history of chlamydia | ||||||
| No | 13 | 7.58 (4.40 to 13.06) | reference | reference | ||
| Yes | 17 | 16.89 (10.50 to 27.16) | 2.19 (1.06 to 4.54) | 0.035 | 2.06 (0.99 to 4.30) | 0.054 |
| Past history of gonorrhoea | ||||||
| No | 14 | 9.19 (5.44 to 15.51) | reference | reference | ||
| Yes | 20 | 13.34 (8.63 to 20.74) | 1.53 (0.77 to 3.06) | 0.226 | 1.75 (0.81 to 3.80) | 0.154 |