Introduction & Objective: Menstrual disorders in early years after menarch are common among the adolescent girls. Menarch age ,has been mentioned as a  factor which effect on menstrual disorders. Therefore the aim of this study was to determine of menstrual disorders and these relationship with menarch age.

Materials & Methods: Is a cross-sectional study which was undertaken on 1000 highschool girls selected randomly from 20 highschools in hamedan, Iran.

Results: The average age of menarch was 13.7yr.the menstrual disturbances were: hypermenorrhea (clot) 73.9%, intermenstrual bleeding(18.4%),hypermenorhea(long bleeding) 15.2% , polymenorrhea 9.1%, oligomenorrhea 5.9% andhypomenorrhea 1.7% prevalence of dysmenorrhea was 78%. There was significant correlation between menarch age and menstruation interval(and its regullarity),intermenstrual bleeding (IMB) and dysmenorrhea (p<0.05).

Conclusion: Menometrorrhagia (in the form of long and heavy bleeding with irregullar intervals and IMB)was the most common manifestation of menstrual disorders. Thus the authers rcommended the evaluating of hormonal and gynecological causes of this disorders and preventing of heavy bleeding complications.generally,considration about adolescents nutrition exercises,public healths and psychotic situation can guaranty thir transition from childhood to adolescence period.