Background Menarche is the stage of entering adulthood and it has a psychological and social side effects. Together with thelarche and adrenarche they make the triad of puberty in females. In Sudan, there are some published papers about age at menarche and some of its associations but the need is there for more.

Objectives We aimed in this study to figure out the mean age at menarche in primary and secondary high school girls in Khartoum north city-Khartoum state, In addition, to correlation of weight, height, plus socioeconomic status with age at menarche.

Methods It was a community based cross-sectional study, conducted from December 2013 to February 2014. The tool used was an interview questionnaire, to collect data from randomly selected primary and secondary high schools, in Khartoum North city. The calculated sample was 367 girls. They were interviewed about their sociodemographic data, their age at first menstruation, plus other related variables. Their weight and height were measured. Data were analyzed using IBM SPSS version 20. The mean age at menarche was calculated and a correlation with Spearman’s coefficient was done between age at menarche and the three variables weight, height and socioeconomic status.

Results the girls mean age at menarche was 12.73 (SD = 0.89) years, there is a weak negative correlation with weight and socioeconomic status, and a weak positive correlation with height.

Conclusion compared with previous studies in Sudan there is a tendency for a decrease in age at menarche, further studies are needed to confirm or oppose this finding.

The authors have declared no competing interest.

This study did not receive any funding

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Ethics committee/IRB of Sudan Medical Specialization Board gave ethical approval for this work

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