Table 2. Reproductive characteristics of the study population.
| Variables | Osteoporosis (n = 673) | Non-osteoporosis (n = 1857) | P value | |
|---|---|---|---|---|
| Age at menarche, years | 16.20 ± 2.01 | 15.70 ± 1.91 | <0.0001 | |
| Age at menopause, years | 50.70 ± 3.09 | 50.82 ± 2.87 | 0.128 1 | |
| Gravidity, n | 5.69 ± 8.78 | 5.58 ± 9.47 | 0.792 | |
| Time from menarche to first delivery, years | 7.77 ± 3.85 | 8.49 ± 3.99 | <0.0001 | |
| Time since menopause, years | 12.07 ± 6.14 | 7.70 ± 5.88 | <0.0001 | |
| Age at first delivery, years | 23.96 ± 3.19 | 24.15 ± 3.33 | 0.207 | |
| First delivery age groups, n (%) | ≤23 years | 310 (46.5%) | 821 (44.6%) | 0.053 |
| 24–29 years | 331 (49.7%) | 903 (49.1%) | ||
| ≥30 years | 25 (3.8%) | 115 (6.3%) | ||
| Time from menarche to first delivery, n (%) | ≤5 years | 199 (30.6%) | 437 (24.2%) | 0.021 |
| 6–10 years | 300 (46.1%) | 860 (47.6%) | ||
| 11–15 years | 134 (20.6%) | 430 (23.8%) | ||
| 16–20 years | 16 (2.5%) | 70 (3.9%) | ||
| 21–25 years | 2 (0.3%) | 8 (0.4%) | ||
| 26–30 years | 0 (0%) | 1 (0%) | ||
| History of breast feeding, n (%) | Yes | 289 (95.1%) | 838 (90.4%) | 0.012 |
| No | 15 (4.9%) | 89 (9.6%) | ||
| Total duration of breast feeding groups, n (%) | ≤24 months | 83 (28.8%) | 368 (44.0%) | <0.0001 |
| 25–48 months | 94 (32.6%) | 265(31.7%) | ||
| 49–72 months | 55 (19.1%) | 112 (13.4%) | ||
| ≥73 months | 56 (19.4%) | 91 (10.9%) | ||
| History of OC use, n (%) | Yes | 147 (21.9%) | 494 (26.7%) | 0.017 |
| No | 523 (78.1%) | 1358 (73.3%) | ||
| History of HT use, n (%) | Yes | 85 (12.7%) | 401 (21.7%) | <0.0001 |
| No | 585 (87.3%) | 1447 (78.3%) | ||
1Mann—Whitney U test was performed for continuous variables that did not show normal distribution.
OC, oral contraceptive; HT, hormone therapy.
Data are presented as the mean ± standard deviation.
P values were obtained using the 2-sample t-test for continuous variables and the chi-square test for categorical variables.