To investigate the timing of puberty onset among primary school students, so as to provide the reference data for early identification of children with suspected precocious puberty.
A study was conducted from October 23 to November 7, 2023, involving 10 225 students(5 412 boys, 4 813 girls) from grade 1 to 6 of four campuses in Meiling Primary School in Yangzhou. Breast development in girls and external genitalia in boys was assessed via visual inspection and palpation, with pubertal stages classified using the Tanner staging method. Puberty onset timing was determined based on age/sex reference values from Chinese Han children's pubertal milestone indicators. Descriptive analysis was performed using SPSS 26.0.
The median age for testicular volume reaching 4 mL in boys was 10.49 years, while the median age for breast development onset in girls was 9.70 years. Among boys with testicular volume ≥4 mL, 16.6%(n=217) were identified as suspected early puberty cases; among girls with Tanner stage Ⅱ and Ⅲ, 123(9.4%) and 165(18.5%) showed earlier breast development than the reference range. Overall, 14.4% of students exhibited suspected precocious puberty.
The onset age of puberty for girls in primary schools of Yangzhou aligns with findings from other regions, while boys show earlier pubertal initiation.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |