Table 2.
Adolescent characteristics and family history of the participants
| Variable | Endometriosis group n=157 |
Control group n=156 |
P value | |||
| Age at menarche (years), mean±1 SD | 12.7±1.5 | 13.0±1.6 | 0.11* | |||
| Missing, n (%) | 1 | (0.6%) | 7 | (4.5%) | ||
| Severe dysmenorrhea in adolescence, n (%) |
Never | 5 | (3.2%) | 30 | (20.1%) | |
| Rarely | 13 | (8.3%) | 36 | (24.2%) | ||
| Sometimes | 31 | (19.9%) | 43 | (28.9%) | <0.001† | |
| Often | 45 | (28.8%) | 21 | (14.1%) | ||
| Always | 62 | (39.7%) | 19 | (12.8%) | ||
| Missing | 1 | (0.6%) | 7 | (4.5%) | ||
| Absenteeism from school due to dysmenorrhea, n (%) |
Never | 28 | (17.8%) | 99 | (66.4%) | |
| Rarely | 23 | (14.6%) | 26 | (17.4%) | ||
| Sometimes | 52 | (33.1%) | 17 | (11.4%) | <0.001† | |
| Often | 38 | (24.2%) | 5 | (3.4%) | ||
| Always | 16 | (10.2%) | 2 | (1.3%) | ||
| Missing | 0 | (0%) | 7 | (4.5%) | ||
| Use of painkillers for dysmenorrhea in adolescence, n (%) |
Never | 20 | (12.8%) | 56 | (37.6%) | |
| Rarely | 15 | (9.6%) | 30 | (20.1%) | ||
| Sometimes | 36 | (23.1%) | 40 | (26.8%) | <0.001† | |
| Often | 39 | (25.0%) | 10 | (6.7%) | ||
| Always | 46 | (29.5%) | 13 | (8.7%) | ||
| Missing | 1 | (0.6%) | 7 | (4.5%) | ||
| Use of oral contraceptives for dysmenorrhea in adolescence, n (%) |
Yes | 60 | (38.2%) | 17 | (11.5%) | <0.001‡ |
| No | 97 | (61.8%) | 131 | (88.5%) | ||
| Missing | 0 | (0%) | 8 | (5.1%) | ||
| Family history of endometriosis, n (%) |
Yes | 42 | (26.8%) | 7 | (4.5%) | <0.001‡ |
| Not yes§ | 115 | (73.2%) | 149 | (95.5%) | ||
*Independent samples t-test.
†Linear-by-linear association χ2 test.
‡Pearson’s χ2 test.
§Not yes: no/irrelevant/missing.