Table 2.
Average age at menarche and percentage of girls who had experienced menarche by age
| Total 2001–2011 |
II 2001 |
III 2005 |
IV 2007–2009 |
V 2010/2011 |
p-value | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Average age at Menarche | |||||||||||
| Mean SE | 12.71 ± 0.03 | 13.40 ± 0.06 | 13.08 ± 0.06 | 12.38 ± 0.04 | 12.38 ± 0.05 | <0.0001 | |||||
| Number of total respondents | |||||||||||
| 3409 | 680 | 576 | 1299 | 854 | |||||||
| Number of respondents experienced menarche | |||||||||||
| 2402 | 460 | 389 | 926 | 627 | |||||||
| Percentage of girls who experienced menarche | |||||||||||
| Age (y) | n | % | n | % | n | % | n | % | n | % | |
| 10.0–10.9 | 461 | 8.0 | 91 | 8.8 | 79 | 5.1 | 174 | 7.5 | 117 | 10.3 | 0.6429 |
| 11.0–11.9 | 446 | 26.7 | 84 | 21.4 | 76 | 15.8 | 176 | 29.0 | 110 | 34.6 | 0.0084 |
| 12.0–12.9 | 410 | 60.0 | 78 | 42.3 | 68 | 63.2 | 174 | 65.5 | 90 | 62.2 | 0.0036 |
| 13.0–13.9 | 422 | 85.3 | 79 | 76.0 | 82 | 80.5 | 148 | 87.8 | 113 | 92.0 | 0.0018 |
| 14.0–14.9 | 403 | 95.8 | 76 | 94.7 | 68 | 95.6 | 161 | 95.7 | 98 | 96.9 | 0.4384 |
| 15.0–15.9 | 347 | 98.0 | 75 | 97.3 | 59 | 96.6 | 133 | 100.0 | 80 | 96.3 | 0.4801 |
| 16.0–16.9 | 331 | 98.8 | 65 | 98.5 | 53 | 98.1 | 125 | 99.2 | 88 | 98.9 | 0.6114 |
| 17.0–17.9 | 341 | 99.4 | 77 | 100.0 | 54 | 98.2 | 114 | 99.1 | 96 | 100.0 | 0.9318 |
| 18.0–18.9 | 248 | 99.2 | 55 | 100.0 | 37 | 97.3 | 94 | 98.9 | 62 | 100.0 | 0.9071 |
Data are expressed as mean ± SE
n: the total number of girls at each age who had answered the status of menarche
%: the percentage of girls who had experienced menarche among girls who had answered the status of menarche question