Key words: Preterm labor, Vaginal progesterone, Prevention, High risk pregnancy. Conflict of Interest: Nill Received: September 23, 2009 Accepted: November 30, 2009

Menstrual disorders cause a lot of problems for the women. Sometimes diagnosis and treatment of these problems seems very sophisticated. Early diagnosis and treatment of menstrual disorders together with its clinical complications, recognition of their underlying causes and their relation with one another, are essential for treatment of these disorders. The aim of this study was to determine the incidence of menstrual disorders and some of its potential causes in 17 and 18 year old high school female students in Sanandaj in 2005. This was a descriptive-analytic cross sectional study and included 511 high school female students at the age of 17 and 18 years. After obtaining primary information, in case of any menstrual disorder, the subjects were referred to a gynecologist for confirmation of the diagnosis. After confirmation of diagnosis sonographic and hormonal studies were performed. Using SPSS software, the data were analyzed by means of descriptive statistics and x2 test. The incidence of menstrual disorders in the study population was 43.25%. Hypermenorrhea was the most and hypomenorrhea was the least common disorders (13.9% and 3.13% respectively). Polymenorrhea was detected in 13.31% of the cases. The incidence rates of dysmenorrhea, premenstrual syndrome (PMS), and spotting were 78.1%, 72.4% and 8.2% respectively. Menstrual disorders and its symptoms showed no significant relationship with presence of any evidence of PCO in sonoghraphy (P>0.05). High incidence of menstrual disorders in high school students should be taken into consideration and necessary instructions should be given to these students to decrease their stress. In case of persistence of the menstrual disorder, hormonal and sonographic examinations should be performed to detect the underlying cause of menstrual disorder.