Table 1.
General characteristics of the participants (n = 8,658).
| Variables | Baseline age (y) | p | |||||||
|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||
| Total (n = 8,658) | < 30 (n = 1,572) | 30–39 (n = 5,142) | ≥ 40 (n = 1,944) | ||||||
| Age (y) | 35.1 | ± 5.8 | 28.3 | ± 0.8 | 33.9 | ± 2.8 | 44.0 | ± 3.2 | < 0.001 |
|
| |||||||||
| Educational level | |||||||||
| 3-year college | 1,696 | (19.6) | 359 | (22.8) | 1,038 | (20.2) | 299 | (15.4) | < 0.001 |
| 4-year college | 5,568 | (64.3) | 1,175 | (74.7) | 3,476 | (67.6) | 917 | (47.2) | |
| ≥ Graduate school | 1,394 | (16.1) | 38 | (2.4) | 628 | (12.2) | 728 | (37.4) | |
|
| |||||||||
| Marital status | |||||||||
| Unmarried | 3,039 | (35.1) | 1,112 | (70.7) | 1,646 | (32.0) | 281 | (14.5) | < 0.001 |
| Married/Cohabiting | 5,472 | (63.2) | 452 | (28.8) | 3,420 | (66.5) | 1,600 | (82.3) | |
| Divorced/Widowed/Separated | 147 | (1.7) | 8 | (0.5) | 76 | (1.5) | 63 | (3.2) | |
|
| |||||||||
| Work experience (y) | |||||||||
| ≤ 1 | 48 | (0.6) | 14 | (0.9) | 27 | (0.5) | 7 | (0.4) | < 0.001 |
| 1–3 | 184 | (2.1) | 85 | (5.4) | 92 | (1.8) | 7 | (0.4) | |
| 3–5 | 714 | (8.2) | 426 | (27.1) | 269 | (5.2) | 19 | (1.0) | |
| 5–10 | 3,358 | (38.8) | 1,041 | (66.2) | 2,244 | (43.6) | 73 | (3.8) | |
| ≥ 10 | 4,354 | (50.3) | 6 | (0.4) | 2,510 | (48.8) | 1,838 | (94.5) | |
|
| |||||||||
| History of pregnancy | |||||||||
| Currently pregnant | 453 | (5.2) | 81 | (5.2) | 368 | (7.2) | 4 | (0.2) | < 0.001 |
| Previous pregnancies | |||||||||
| 1 | 1,750 | (20.2) | 181 | (11.5) | 1,287 | (25.0) | 282 | (14.5) | < 0.001 |
| 2 | 1,913 | (22.1) | 50 | (3.2) | 1,119 | (21.8) | 744 | (38.3) | |
| ≥ 3 | 953 | (11.0) | 9 | (0.6) | 441 | (8.6) | 503 | (25.9) | |
|
| |||||||||
| Current menstrual regularity | |||||||||
| Very regular (± 3 d) | 2,806 | (32.4) | 418 | (26.6) | 1,715 | (33.4) | 673 | (34.6) | < 0.001 |
| Regular (± 5–7 d) | 3,621 | (41.8) | 664 | (42.2) | 2,195 | (42.7) | 762 | (39.2) | |
| Irregular | 1,226 | (14.2) | 300 | (19.1) | 653 | (12.7) | 273 | (14.0) | |
| Very irregular | 447 | (5.2) | 112 | (7.1) | 257 | (5.0) | 78 | (4.0) | |
| Amenorrhea, oral contraception, within 6 months of child birth, or breastfeeding | 558 | (6.4) | 78 | (5.0) | 322 | (6.3) | 158 | (8.1) | |
|
| |||||||||
| Menstrual pain | 5,689 | (65.7) | 1,217 | (77.4) | 3,532 | (68.7) | 940 | (48.4) | < 0.001 |
| Severity* | 5.4 | ± 1.8 | 5.7 | ± 1.8 | 5.5 | ± 1.8 | 5.0 | ± 1.8 | < 0.001 |
| Impact on daily activities† | 4.6 | ± 2.1 | 4.8 | ± 2.1 | 4.7 | ± 2.1 | 4.1 | ± 2.0 | < 0.001 |
|
| |||||||||
| Type of menstrual hygiene products | |||||||||
| Disposable menstrual pad | 7,704 | (89.0) | 1,368 | (87.0) | 4556 | (88.6) | 1,780 | (91.6) | < 0.001 |
| Cloth menstrual pad | 387 | (4.5) | 66 | (4.2) | 254 | (4.9) | 67 | (3.4) | |
| Tampon | 364 | (4.2) | 94 | (6.0) | 212 | (4.1) | 58 | (3.0) | |
| Menstrual cup | 136 | (1.6) | 37 | (2.4) | 86 | (1.7) | 13 | (0.7) | |
| Others (such as menstrual panty) | 67 | (0.8) | 7 | (0.4) | 34 | (0.7) | 26 | (1.3) | |
Data are presented as mean ± SD or n (%).
*
10-point scale: 1 = no pain at all; 10 = extreme pain.
†
10-point scale: 1 = no trouble at all; 10 = very troublesome.