Table II.
Comparison of menstrual and reproductive factors between case and control groups
| Variable | Levels | Control group (n = 153) | Stage I/II endometriosis (n = 122) | Stage III/IV endometriosis (n = 128) | Value of p | Crude OR* (95% CI) Any stage | Crude OR** (95% CI) Stage III/IV |
|---|---|---|---|---|---|---|---|
| Age at menarche [years] | 13.42 ±1.42 | 13.62 ±1.54 | 13.22 ±1.39 | 0.089 | 0.998 (0.870-1.147) | 0.903 (0.763-1.069) | |
| Menstrual pattern | Regular | 108 (34.5%) | 97 (31.0%) | 108 (34.5%) | 0.019 | 1† | 1† |
| Irregular | 45 (50.0%) | 25 (27.8%) | 20 (22.2%) | 0.527 (0.328-0.847) | 0.444 (0.246-0.802) | ||
| Duration of menstrual bleeding [days] | 5.99 ±1.49a | 5.97 ±1.37a | 6.63 ±2.75b | 0.009 | 1.099 (0.975-1.238) | 1.178 (1.026-1.351) | |
| Dysmenorrhea | Absent | 12 (54.5%) | 3 (13.6%) | 7 (31.8%) | 0.149 | 1† | 1† |
| Present | 141 (37.0%) | 119 (31.2%) | 121 (31.8%) | 2.043 (0.86-4.849) | 1.471 (0.561-3.855) | ||
| Severity of dysmenorrhea | No pain | 12 (54.5%) | 3 (13.6%) | 7 (31.8%) | 0.031 | 1† | 1† |
| Mild | 69 (42.3%) | 54 (33.1%) | 40 (24.5%) | 1.635 (0.668-4.000) | 0.994 (0.362-2.729) | ||
| Moderate | 41 (38.0%) | 32 (29.6%) | 35 (32.4%) | 1.961 (0.778-4.944) | 1.463 (0.520-4.122) | ||
| Severe | 31 (28.2%) | 33 (30.0%) | 46 (41.8%) | 3.058 (1.199-7.800) | 2.544 (0.901-7.179) | ||
| Amount of menstrual bleeding | Low | 13 (26.5%) | 15 (30.6%) | 21 (42.9%) | 0.001 | – | – |
| Intermediate | 120 (44.9%) | 70 (26.2%) | 77 (28.8%) | 0.442 (0.224-0.872) | 0.397 (0.188-0.840) | ||
| High | 20 (23.3%) | 37 (43.0%) | 29 (33.7%) | 1.192 (0.531-2.673) | 0.898 (0.366-2.199) | ||
| Duration of menstrual cycle [days] | 29.80 ±8.83a | 28.43 ±3.56ab | 27.87 ±5.65b | 0.043 | 0.963 (0.933-0.994) | 0.963 (0.928-0.999) | |
| Spotting | No | 105 (41.2%) | 80 (31.4%) | 70 (27.5%) | 0.044 | 1† | 1† |
| Yes | 48 (32.4%) | 42 (28.4%) | 58 (39.2%) | 1.458 (0.953-2.231) | 1.812 (1.113-2.951) | ||
| Duration of spotting [days] | 0.74 ±1.37a | 0.84 ±1.36ab | 1.19 ±1.64b | 0.031 | 1.149 (0.992-1.331) | 1.222 (1.040-1.437) | |
| Age at first intercourse [years] | 20.90 ±3.91a | 22.21 ±3.93b | 23.25 ±5.48b | < 0.001 | 1.103 (1.049-1.159) | 1.114 (1.055-1.176) | |
| Dyspareunia | No | 103 (44.4%) | 63 (27.2%) | 66 (28.4%) | 0.008 | 1† | 1† |
| Yes | 50 (29.2%) | 59 (34.5%) | 62 (36.3%) | 1.932 (1.271-2.938) | 1.935 (1.193-3.140) | ||
| Contraceptive use | No | 94 (47.0%) | 57 (28.5%) | 49 (24.5%) | < 0.001 | 1† | 1† |
| Yes | 59 (29.1%) | 65 (32.0%) | 79 (38.9%) | 2.164 (1.435-3.264) | 2.569 (1.585-4.162) | ||
| Age at first pregnancy [years] | 24.25 ±4.86 | 26.48 ±4.99 | 24.84 ±5.45 | 0.227 | 1.059 (0.961-1.168) | 1.023 (0.921-1.137) | |
| History of live birth | No | 145 (38.8%) | 114 (30.5%) | 115 (30.7%) | 0.267 | 1† | 1† |
| Yes | 8 (27.6%) | 8 (27.6%) | 13 (44.8%) | 1.662 (0.717-3.852) | 2.049 (0.821-5.111) | ||
| Age at first delivery [years] | 22.5 ±5.18 | 25.75 ±3.85 | 23.0 ±4.06 | 0.274 | 1.091 (0.894-1.331) | 1.028 (0.835-1.266) | |
| Previous abortion | No | 136 (40.5%) | 96 (28.6%) | 104 (31.0%) | 0.058 | 1† | 1† |
| Yes | 17 (25.4%) | 26 (38.8%) | 24 (35.8%) | 2.000 (1.107-3.615) | 1.846 (0.943-3.614) | ||
| Type of abortion | Spontaneous | 15 (25.4%) | 23 (39.0%) | 21 (35.6%) | 1.000 | 1† | 1† |
| Induced | 2 (25.0%) | 3 (37.5%) | 3 (37.5%) | 1.023 (0.186-5.622) | 1.071 (0.159-7.221) | ||
| History of curettage | No | 145 (39.2%) | 107 (28.9%) | 118 (31.9%) | 0.065 | 1† | 1† |
| Yes | 7 (21.9%) | 15 (46.9%) | 10 (31.3%) | 2.302 (0.970-5.459) | 1.755 (0.648-4.753) | ||
| Ectopic pregnancy | No | 152 (38.5%) | 117 (29.6%) | 126 (31.9%) | 0.116 | 1† | 1† |
| Yes | 1 (12.5%) | 5 (62.5%) | 2 (25.0%) | 4.379 (0.533-35.938) | 2.413 (0.216-26.918) | ||
| Pelvic pain | No | 151 (41.5%) | 108 (29.7%) | 105 (28.8%) | < 0.001 | 1† | 1† |
| Yes | 2 (5.1%) | 14 (35.9%) | 23 (59.0%) | 13.115 (3.113-55.247) | 16.538 (3.817-71.656) | ||
| Feeling of abdominal mass | No | 153 (39.6%) | 113 (29.3%) | 120 (31.1%) | 0.004 | 1† | 1† |
| Yes | 0 (0.0%) | 9 (52.9%) | 8 (47.1%) | 23.009 (1.373-385.45)‡ | 21.66 (1.24-378.96)‡ |
*
Odds ratio for comparing any type of endometriosis with control group
**
Odds ratio for comparing severe endometriosis patients with control group
a,b
The same letters indicate no statistical significance based on the Tukey HSD multiple comparison procedure
†
Reference category
‡
Adjusted OR for zero cell count was calculated using Agresti (2007) method [23]