Background and Aim: Androgenetic alopecia is an extremely common disorder affecting both men and women. The incidence is generally considered to be greater in males than females, although some evidence suggests that the apparent differences in incidence may be a reflection of different expression in males and females. This genetically determined disorder is progressive through the gradual conversion of terminal hairs into indeterminate hairs and finally to vellus hairs. Patients have a reduction in the terminal-to-vellus hair ratio, normally at least 2:1. Following miniaturization of the follicles, fibrous tracts remain. Patients with this disorder usually have a typical distribution of hair loss.
Methods: This is a cross sectional study that conducted in Isfahan health center in 2007-2008 .Using simple random sampling, we selected 1800 women in urban health center areas for hair loss. We evaluated the type of hair loss by Ludwig classification. The data was collected through administration of a specifically designed questionnaire and was analyzed using SPSS software. The chi-square and student tests were used for data analysis.

Results: According to results of this study the of 1800 women, 712 (39.6%) had hair loss. Mean age of females who had hair loss was 50.4±13 years.
Conclusion: Thyroid disorders, ferritin serum level and androgenic hormones may play role in hair loss and their existance should be assessed.