Age at menarche and associated factors of female junior middle school students in Tianjin area

Abstract

Objective This study aims to investigate the menarcheal age of female junior middle school students in Tianjin and associated factors, providing suggestions for further development of adolescence education on physiological and mental health.

Methods A total of 4 127 junior middle school girls in Tianjin area were selected by stratified random sampling method, and investigated by the method of physical examination and questionnaire survey, results were analyzed.

Results There were 1 383 girls reported menarche. Mean age at menarche was (12.68±1.19) years old; One-way ANOVA showed that girls with higher family income, higher parental education had earlier menarcheal age ( F = 4.97, 9.52, 10.64, P<0.05). It showed that the tendency that obesity group and over-weight group was higher in the rate of menarche than that of normal group and marasmus group ( F = 4.20, P< 0.05). However, different time on watching TV, computer or celephone and sleeping was found to be unrelated with age at menarche ( P>0.05). Kruskal Wallis H test showed that girls whose mothers’ AAM was earlier had earlier menarcheal age ( H =82.94, P< 0.05). According to age, girls were divided into groups of 10–11, 11–12, 12–13 and 13–14 years old. Girls in each age group were divided into the menstruation menarche group and the non-menstruation menarche group. The results showed that the levels of height, weight, BMI, waist circumference, hip circumference, and the skin fold thickness in menstruation group were higher than those in non-menstruation group ( t = 2.18–10.93, P<0.05). After that, girls of each group were divided into four group: marasmus group, the normal group, the over-weight group and the obesity group according to BMI (χ ² = 34.66, 13.37, 11.09, 12.60, P<0.05).

Conclusion Female junior middle school students’ menarcheal age in Tianjin is related to family income, parents’ education, mother’ s age at menarche, obesity and physical exercise frequency.

Abstract

【摘要】 目的 调査天津地区中小学女生月经初潮情况及其相关因素, 为指导青春期女生生理发育和开展心理健康 教育提供依据。 方法 采取随机分层整群抽样方法, 对天津地区 4 127 名中小学女生进行问卷调査及体格检査, 并对结果 进行统计学分析。 结果 共有 1 383 名女生经历月经初潮, 平均初潮年龄为 (12.68±1.19) 岁; 单因素方差分析发现, 家庭收 人较髙、父母文化程度较髙的女生, 初潮年龄较小 ( F 值分别为4.97, 9.52, 10.64, P 值均<0.05)。体育锻炼频率越髙的女生 平均初潮年龄越小 ( F = 4.20, P<0.05)。不同看电子产品时间及睡眠时长的女生初潮年龄差异无统计学意义 ( P 值均> 0.05)。经 Krnskal Wallis H 检验, 母亲初潮年龄越小, 女生初潮年龄的中位数越小 ( H = 82.94, P<0.05)。将各年龄组女生分 为已潮组及未潮组, 来潮组女生的身髙、体重、体质量指数 (BMI)、腰围、臀围及皮褶厚度的均值均髙于未来潮组 ( t = 2.18~ 10.93, P 值均<0.05); 将不同年龄组女生根据BMI分为消瘦组、正常组、超重组及肥胖组, 经妒检验, 各年龄组月经来潮率 肥胖组及超重组>正常组>消瘦组, 差异具有统计学意义 (χ ² 值分别为 34.66, 13.37, 11.09, 12.60, P 值均<0.05)。 结论 天 津地区女中小学生月经初潮年龄与家庭收人、父母文化程度、母亲初潮年龄、肥胖、体育锻炼频率等相关。