OBJECTIVETo explore the association between early menarche with anthropometry measurements among adolescent girls in China.

METHODSResearch material was selected from the data of 2010 Chinese National Surveys on Students Constitution and Health. Probability unit regression method was used to calculate the age of 10th percentile (P 10) at menarche and menarche age before the P 10 was defined as early menarche(9.0-11.6 years old). A total of 1072 girls with early menarche were screened. Each girl with early menarche was frequency matched with two girls who hadn't achieved menarche and with the age difference less than 0.1 yr and from the same urban or rural locations. A total of 2144 girls without menarche were screened. Participants' data of height, weight, sitting height, chest circumference, body mass index(BMI) and height and sitting height index were analyzed. t test and wilcoxon test were used to analyze the anthropometry measurements differences between the two groups, Chi square test was used to analyze the differences of overweight and obesity between the two groups. Multilevel model was used to explore the association between early menarche with anthropometry measurements and overweight and obesity.

RESULTSA total of 1072 girls with early menarche and 2144 girls without menarche. Early menarche girls' height, sitting height, chest circumference, weight and BMI were (151.42 ± 7.46) cm, (80.86 ± 4.21) cm, (73.88 ± 7.72) cm, (44.32 ± 9.35) kg, and (19.18 ± 3.03) kg/m(2), while they were (144.86 ± 7.55) cm, (76.96 ± 4.05) cm, (67.25 ± 6.94) cm, (36.07 ± 7.88) kg and (16.64 ± 2.48) kg/m(2) in girls without menarche. The difference between two groups were significant(Z values were -22.20, -23.69, -24.38, -23.12, -20.17, -6.33 respectively with all P values < 0.01). Multilevel analysis results showed that in 9.0-11.6 years old girls early menarche was associated with anthropometry measurements(all P values < 0.05). Compared with girls without menarche, girls with early menarche had a relative higher height, sitting height, weight, chest circumference, with increments of 5.28 cm, 3.37 cm, 5.53 cm, 6.37 kg, 1.79 kg/m(2). Within subgroup analysis, there were parabolic trends with age in the height, weight and sitting height differences and "U" trend in chest circumference difference between girls with early menarche and girls without menarche.In 9.0-10.8 years old, 10.9-11.0 years old and 11.1-11.2 years old groups, the risk of overweight and obesity among girls with early menarche were 2.98 (95%CI:1.92-4.63) times, 6.76 (95%CI:2.79-16.39) times, 2.99 (95%CI:1.40-6.40) times of girls without menarche.

CONCLUSIONThe early onset of menarche is related with height, sitting height, weight and chest circumference, and it is closely associated with overweight and obesity among adolescent girls in China.